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Tuned input
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I really like this option:?
? ?- code is available -? ? ?- parts kits are orderable from a number of sources, including amazon (get it in maybe two days!), aliexpress, etc. search for AT-100. Could be as low as 21.xx from Aliexpress ? ?- testable outside of the amp (put varying loads representing your amplifier input on the output of the ATU100 to see how well they're matched) ? ?- I *think* some models actually show the values of L and C used to match so... you could make a fixed network if you like. Consider the price of the kit a "test instrument" for determining values for your manually switched network. -Brian N9ADG |
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Here's a late entry to your options: Get one of the ATU kits that are readily available online, running the software from N7DDC.? Modify the HW, and/or the SW. But you have all of the pieces you need in the kits.
software: hardware: just one of MANY available from AMZN:? Or from AliExpress:? I've ordered and built the ATU-100's in the past, they work quite well -- I've used them with QRP radios (e.g. QDX from QRP-labs), as well as a k3 with no tuner.? -Brian N9ADG |
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I guess I don't understand. Your suggesting to install this tuner inside the RF deck?? How will you control it?? How will you switch it to difference bands?How will you prevent it from tuning as you transmit??? on a Grounded grid amplifier, the impedance changes
drastically as you add drive and adjust the output power.? ? On this particular map it could be 1.5 to 3 to 1 depending on drive and tuning.
From: [email protected] <[email protected]> on behalf of Brian Moran via groups.io <brian.moran@...>
Sent: Sunday, December 31, 2023 9:35 AM To: [email protected] <[email protected]> Subject: Re: [ham-amplifiers] Tuned input ?
Here's a late entry to your options: Get one of the ATU kits that are readily available online, running the software from N7DDC.? Modify the HW, and/or the SW. But you have all of the pieces you need in the kits.
software: hardware: just one of MANY available from AMZN:? Or from AliExpress:? I've ordered and built the ATU-100's in the past, they work quite well -- I've used them with QRP radios (e.g. QDX from QRP-labs), as well as a k3 with no tuner.? -Brian N9ADG |
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Yes, you would mount the tuner inside your amplifier somewhere; the output of the input network should be close to the tube. Controls for the tuner, and potentially the display, would be on the front panel. ? |
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I have tried this in the past. It's a huge KLUDGE and would not recommend it.? That tuner is going to try to tune while you are transmitting, You're constantly showing your radio a bad match every time you change frequency as it has to retune.?
Unless you can somehow make it stop with hard ware or software it never works.??
The old LDG amplifier version had special code that made it work for an amplifier and it had board changes as we only need a small change to work with cathode drive.
Then, The biggest issue, Is the Q is never correct.? The Q is important here for properly function and flywheel effect.? The antenna tuner is never going to match the correct Q.? It's super narrow and will have to retune even with slight changes in frequency.?
If you jump from 14.100 to 14.250 its gonna ratchet away as you try to make a contact OR if its disabled, the SWR on the input will be 6 to 1.
What people end up doing is to remove the AUTO portion and just hard wire the relays for each band.? At that point, Just build a board and tune it.
C
From: [email protected] <[email protected]> on behalf of Brian Moran via groups.io <brian.moran@...>
Sent: Sunday, December 31, 2023 7:17 PM To: [email protected] <[email protected]> Subject: Re: [ham-amplifiers] Tuned input ?
Yes, you would mount the tuner inside your amplifier somewhere; the output of the input network should be close to the tube. Controls for the tuner, and potentially the display, would be on the front panel. ? |
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Mike.? I ordered the board from Fred at FAR.? He did not have relays or the trimmers. I found the relays and have ordered them.?? |
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Arco was the big name in variable caps at one time. Not sure if they are still around. I wonder if there are any articles on that board? I see the original designer has passed. Mike
On Tuesday, January 2, 2024 at 12:37:28 PM EST, W7WRX <clark@...> wrote:
Mike.? I ordered the board from Fred at FAR.? He did not have relays or the trimmers. I found the relays and have ordered them.?? |
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I see a quantity on Ebay but they are a small fortune. Not what I expected.
On Tuesday, January 2, 2024 at 12:37:28 PM EST, W7WRX <clark@...> wrote:
Mike.? I ordered the board from Fred at FAR.? He did not have relays or the trimmers. I found the relays and have ordered them.?? |
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Everything is in bound. I found the relays and made an offer on the trimmers and the seller accepted.? Going to have 125 bucks or so into this.? Will probably need some mica caps also. I have some, Fred sent some. We will see.??
Should be able to start the build next week.?
This will be interesting.? I took drive power/output power/IMD/GAIN/ efficiency plots of the amplifier without the input.? Let's see what the fly wheel effect does back-to-back.
I do need to order some micro switches.? On this amp there is no 10-meter 24-volt signal. The 10/15 share a band position.? It uses a roller.? I will need to mount the micro switch to the roller or drive system to click in the 10 meter input and drop the 15-meter
input when the roller gets past 15 one its way to 10 meters.
C From: [email protected] <[email protected]> on behalf of mike repinski via groups.io <mikflathead@...>
Sent: Tuesday, January 2, 2024 11:35 AM To: [email protected] <[email protected]> Subject: Re: [ham-amplifiers] Tuned input ?
I see a quantity on Ebay but they are a small fortune. Not what I expected.
On Tuesday, January 2, 2024 at 12:37:28 PM EST, W7WRX <clark@...> wrote:
Mike.? I ordered the board from Fred at FAR.? He did not have relays or the trimmers. I found the relays and have ordered them.?? |
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I got all the parts in and am building the board.
I installed all the relays, the 10 meter A and B trimmers and the wound a toroid. 7 turns of 20 AWG With a dummy load on output of 50 ohms and the analyzer on the input: with 10 meter relay closed, I can tune the trimmers to get a dip of 1.0 at 56 ohms 28.500.? ?I am using LESS cap than the Chart says. It says 100PF, 7 turns and 100PF.? I am at 25 to 35 PF on each in and out cap. QuestionL What is the expected behavior if I roll the Analyzer down to 20 meters?? ? I do NOT SEE A BAND PASS for the 10 meter position. I only see matching and a HIGH PASS.? If I try to go past 40MHZ the SWR shoots up high. If I go LOWER in frequency the impedance will move but its fairly flat Is this expected bahavior???? C |
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On Mon, Jan 15, 2024 at 12:26 AM, W7WRX wrote:
<I got all the parts in and am building the board. ## I design and run the PI tuned inputs through software every other week...then verify on the bench.? For a overall network Q? of '4'? (input Q = 2....and output Q =2)? ?on 10m,(28.5 mhz) when matching 50 ohms from xcvr to 50 ohm tube input Z....?it should be 223.4 pf? - .22 uh? - 223.4 pf.? ## For an overall network Q of? ? '1.8'? (input Q =.9......and output Q = .9) on 28.5 mhz, it's then 100 pf - .28 uh - 100 pf.? ? ##? if ur caps are only 25-35 pf, then ur Q is through the floor...and the coil has way too much uh.? ? ## either remove a turn or maybe 2, and? / or spread the turns? a bit.? Tweak the coil till both caps are in the 100-140 pf range.? Ok, at that point, you will see the 1:1 swr @ 28.5 mhz..... which should remain flat between? 28.0? and 29,0...then rise when u go below 28 mhz...and above 29 mhz. ? ##? with the Q through the floor, it all goes to hell...and you won't get a? proper bandpass response.? ? ## Have u tested al the other bands yet ?? ? IE: installed caps and toroid's for the other bands...and tested other bands.? ? ##? Note on the above,? only when matching 50 ohms to 50 ohms? (or any 2 x equal Z's)? is the C1 + C2 caps both the same value.? On software, we only tweak the overall network Q.? ?The C1 input Q? ?+ the C2 output Q = overall network Q.? ##? For a PI network for the kw output side, (High tube Z? down to 50 ohms), typ an Overall network Q of....'12' is used....which consist of an input Q of 10...and an output Q of 2.?? ##? In the old ARRL books (and also Eimac's? 'care + feeding'), they only used the INPUT Q...which is why they said? to use a Q of? '10'.? ?They did the same thing with PI tuned inputs.? When they said to use a Q of..'2'? ?what they really meant was to use an overall network Q of 4.? ? ##? For tuned inputs that are tweaked once ..in the middle of the band,? you want low swr? across the entire band.? ?500 khz on 80m is like 1mhz wide on 40m..and 2 mhz wide on 20m..and 4 mhz wide on 10m.? This is where you can do some creative tweaking.? Each band is different....with 160m only 200 khz? wide, 80m = 500 khz, 40m = 300 khz, 30m = 50 khz,? 20m = 350 khz, 17m = 100 khz, 15m = 450 khz, 12m = 100 khz, 10m = 1700 khz.? ( 6m = 4000 khz). ? ## here is the other thing u gotta worry about.? The tube's input C? is directly in parallel with the C2 of the tuned input. Say a 3CX-3000A7.... with it's 38 pf input C (grid to cathode C).? Now you have to subtract 38 pf from the calculated C2 values of ALL the various tuned inputs for each band.? ##? here's the other thing to deal with.... the XL of the bifilar fil choke (since it's RF grnded at it's cold end...and hot end of fil choke goes to the cathode) is also directly in parallel with the tube's input cathode to grid C.? ##? On a SB-220, they used a 9 uh (per winding) fil choke.? ?XL @ 3.75 mhz =? 212 ohms.? ?You now require 212 ohms of XC to cancel out the XL.? ? 200 pf @ 3.750 mhz = 212 ohms of XC.? On an SB-220, the C2 cap of the 75m tuned input has to be increased by 200 pf? vs it's calculated value.? But since the tube's input C on a pair of 3-500Z's is 16.6 pf,? it's then 200-16.6 pf =? 183.4 pf. ## The fil choke primarily affects the lower bands. On the upper bands it's less of an issue.? ? 9 uh is 1611 ohms of XL @ 28.5 mhz.? ? ? 3.465 pf = 1611 ohms of XC.? ? ?That amounts to dick on 28.5 mhz...and the pair of 3-500Z's still has 16.6 pf...so now it's 16.6 - 3.465 pf = 13.135 pf.? 13.135 pf has to be subtracted from the calculated C value of the tuned input. ? ##? If you are doing say a PI network for a 3CX-3000A7,? wire the relay switched tuned input? into the cathode.....and temp wire a 50 ohm resistor between one cathode lug....and chassis....and also plug the tube into the socket.? With no fil or B+, all voltages off....and TR relays activated, put ur analyzer on the input...and tweak both arco's for each band for 1:1 swr.? ?50 ohm resistor removed.? Apply B+ and fil V.... and test the amp.? ? It will be sorta close, and perhaps some minor C1 + C2 tweaking required.? That depends on drive level, bias used,? loaded B+ used, amp tuned to max PO.... and perhaps loading increased till PO drops 1-2%, and cable length between xcvr and input to amp.? ##? if the relay switched, tuned input board is below the chassis, near the cathode, it may or may not be possible to tweak all the arco caps.? ?The board would have to be mounted to rear apron, with holes to access the caps..or to chassis..pita. If amp is fan cooled, you might be able to remove bottom lid.? If a chimney is used, removal of bottom lid means? zero airflow.?? ? ##? This is why I went to the pair of broadcast caps + tapped coil, manually tuned, tuned input setup on the hb amps.? ? Jim? ?VE7RF |
开云体育I removed 2 turns and still do not see band pass.? What I see is a high pass at 40mhz.? Below that it's pretty flat down the bands.? ?
It's supposed to be 7 turns of 20awg.?
Do the wire ends as they loop over the donut count as a turn?
C
On Jan 15, 2024 7:27 AM, "Jim VE7RF via groups.io" <jim.thom@...> wrote:
On Mon, Jan 15, 2024 at 12:26 AM, W7WRX wrote:
<I got all the parts in and am building the board. ## I design and run the PI tuned inputs through software every other week...then verify on the bench.? For a overall network Q? of '4'? (input Q = 2....and output Q =2)? ?on 10m,(28.5 mhz) when matching 50 ohms from xcvr to 50 ohm tube input Z....?it should be 223.4 pf? - .22 uh? - 223.4 pf.? ## For an overall network Q of? ? '1.8'? (input Q =.9......and output Q = .9) on 28.5 mhz, it's then 100 pf - .28 uh - 100 pf.? ? ##? if ur caps are only 25-35 pf, then ur Q is through the floor...and the coil has way too much uh.? ? ## either remove a turn or maybe 2, and? / or spread the turns? a bit.? Tweak the coil till both caps are in the 100-140 pf range.? Ok, at that point, you will see the 1:1 swr @ 28.5 mhz..... which should remain flat between? 28.0? and 29,0...then rise when u go below 28 mhz...and above 29 mhz. ? ##? with the Q through the floor, it all goes to hell...and you won't get a? proper bandpass response.? ? ## Have u tested al the other bands yet ?? ? IE: installed caps and toroid's for the other bands...and tested other bands.? ? ##? Note on the above,? only when matching 50 ohms to 50 ohms? (or any 2 x equal Z's)? is the C1 + C2 caps both the same value.? On software, we only tweak the overall network Q.? ?The C1 input Q? ?+ the C2 output Q = overall network Q.? ##? For a PI network for the kw output side, (High tube Z? down to 50 ohms), typ an Overall network Q of....'12' is used....which consist of an input Q of 10...and an output Q of 2.?? ##? In the old ARRL books (and also Eimac's? 'care + feeding'), they only used the INPUT Q...which is why they said? to use a Q of? '10'.? ?They did the same thing with PI tuned inputs.? When they said to use a Q of..'2'? ?what they really meant was to use an overall network Q of 4.? ? ##? For tuned inputs that are tweaked once ..in the middle of the band,? you want low swr? across the entire band.? ?500 khz on 80m is like 1mhz wide on 40m..and 2 mhz wide on 20m..and 4 mhz wide on 10m.? This is where you can do some creative tweaking.?
Each band is different....with 160m only 200 khz? wide, 80m = 500 khz, 40m = 300 khz, 30m = 50 khz,? 20m = 350 khz, 17m = 100 khz, 15m = 450 khz, 12m = 100 khz, 10m = 1700 khz.? ( 6m = 4000 khz). ? ## here is the other thing u gotta worry about.? The tube's input C? is directly in parallel with the C2 of the tuned input. Say a 3CX-3000A7.... with it's 38 pf input C (grid to cathode C).? Now you have to subtract 38 pf from the calculated C2 values of ALL the various tuned inputs for each band.? ##? here's the other thing to deal with.... the XL of the bifilar fil choke (since it's RF grnded at it's cold end...and hot end of fil choke goes to the cathode) is also directly in parallel with the tube's input cathode to grid C.? ##? On a SB-220, they used a 9 uh (per winding) fil choke.? ?XL @ 3.75 mhz =? 212 ohms.? ?You now require 212 ohms of XC to cancel out the XL.? ? 200 pf @ 3.750 mhz = 212 ohms of XC.? On an SB-220, the C2 cap of the 75m tuned input has to be increased by 200 pf? vs it's calculated value.? But since the tube's input C on a pair of 3-500Z's is 16.6 pf,? it's then 200-16.6 pf =? 183.4 pf. ## The fil choke primarily affects the lower bands. On the upper bands it's less of an issue.? ? 9 uh is 1611 ohms of XL @ 28.5 mhz.? ? ? 3.465 pf = 1611 ohms of XC.? ? ?That amounts to dick on 28.5 mhz...and the pair of 3-500Z's still has 16.6 pf...so now it's 16.6 - 3.465 pf = 13.135 pf.? 13.135 pf has to be subtracted from the calculated C value of the tuned input. ? ##? If you are doing say a PI network for a 3CX-3000A7,? wire the relay switched tuned input? into the cathode.....and temp wire a 50 ohm resistor between one cathode lug....and chassis....and also plug the tube into the socket.? With no fil or B+, all voltages off....and TR relays activated, put ur analyzer on the input...and tweak both arco's for each band for 1:1 swr.? ?50 ohm resistor removed.? Apply B+ and fil V.... and test the amp.? ? It will be sorta close, and perhaps some minor C1 + C2 tweaking required.? That depends on drive level, bias used,? loaded B+ used, amp tuned to max PO.... and perhaps loading increased till PO drops 1-2%, and cable length between xcvr and input to amp.? ##? if the relay switched, tuned input board is below the chassis, near the cathode, it may or may not be possible to tweak all the arco caps.? ?The board would have to be mounted to rear apron, with holes to access the caps..or to chassis..pita. If amp is fan cooled, you might be able to remove bottom lid.? If a chimney is used, removal of bottom lid means? zero airflow.?? ? ##? This is why I went to the pair of broadcast caps + tapped coil, manually tuned, tuned input setup on the hb amps.? ? Jim? ?VE7RF |
开云体育If a wire goes through the center of a toroid, it counts and acts as a turn. It does not need to be looped around. 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ? From: [email protected] <[email protected]> On Behalf Of W7WRX
Sent: Monday, January 15, 2024 10:25 AM To: [email protected] Subject: Re: [ham-amplifiers] Tuned input ? I removed 2 turns and still do not see band pass.? What I see is a high pass at 40mhz.? Below that it's pretty flat down the bands.? ? ? It's supposed to be 7 turns of 20awg.? ? Do the wire ends as they loop over the donut count as a turn? ? C ? On Jan 15, 2024 7:27 AM, "Jim VE7RF via groups.io" <jim.thom@...> wrote: On Mon, Jan 15, 2024 at 12:26 AM, W7WRX wrote:
## I design and run the PI tuned inputs through software every other week...then verify on the bench.? For a overall network Q? of '4'? (input Q = 2....and output Q =2)? ?on 10m,(28.5 mhz) when matching 50 ohms from xcvr to 50 ohm tube input Z....?it should be 223.4 pf? - .22 uh? - 223.4 pf.? ## For an overall network Q of? ? '1.8'? (input Q =.9......and output Q = .9) on 28.5 mhz, it's then 100 pf - .28 uh - 100 pf.? ? ##? if ur caps are only 25-35 pf, then ur Q is through the floor...and the coil has way too much uh.? ? ## either remove a turn or maybe 2, and? / or spread the turns? a bit.? Tweak the coil till both caps are in the 100-140 pf range.? Ok, at that point, you will see the 1:1 swr @ 28.5 mhz..... which should remain flat between? 28.0? and 29,0...then rise when u go below 28 mhz...and above 29 mhz. ? ##? with the Q through the floor, it all goes to hell...and you won't get a? proper bandpass response.? ? ## Have u tested al the other bands yet ?? ? IE: installed caps and toroid's for the other bands...and tested other bands.? ? ##? Note on the above,? only when matching 50 ohms to 50 ohms? (or any 2 x equal Z's)? is the C1 + C2 caps both the same value.? On software, we only tweak the overall network Q.? ?The C1 input Q? ?+ the C2 output Q = overall network Q.? ##? For a PI network for the kw output side, (High tube Z? down to 50 ohms), typ an Overall network Q of....'12' is used....which consist of an input Q of 10...and an output Q of 2.?? ##? In the old ARRL books (and also Eimac's? 'care + feeding'), they only used the INPUT Q...which is why they said? to use a Q of? '10'.? ?They did the same thing with PI tuned inputs.? When they said to use a Q of..'2'? ?what they really meant was to use an overall network Q of 4.? ? ##? For tuned inputs that are tweaked once ..in the middle of the band,? you want low swr? across the entire band.? ?500 khz on 80m is like 1mhz wide on 40m..and 2 mhz wide on 20m..and 4 mhz wide on 10m.? This is where you can do some creative tweaking.? Each band is different....with 160m only 200 khz? wide, 80m = 500 khz, 40m = 300 khz, 30m = 50 khz,? 20m = 350 khz, 17m = 100 khz, 15m = 450 khz, 12m = 100 khz, 10m = 1700 khz.? ( 6m = 4000 khz). ? ## here is the other thing u gotta worry about.? The tube's input C? is directly in parallel with the C2 of the tuned input. Say a 3CX-3000A7.... with it's 38 pf input C (grid to cathode C).? Now you have to subtract 38 pf from the calculated C2 values of ALL the various tuned inputs for each band.? ##? here's the other thing to deal with.... the XL of the bifilar fil choke (since it's RF grnded at it's cold end...and hot end of fil choke goes to the cathode) is also directly in parallel with the tube's input cathode to grid C.? ##? On a SB-220, they used a 9 uh (per winding) fil choke.? ?XL @ 3.75 mhz =? 212 ohms.? ?You now require 212 ohms of XC to cancel out the XL.? ? 200 pf @ 3.750 mhz = 212 ohms of XC.? On an SB-220, the C2 cap of the 75m tuned input has to be increased by 200 pf? vs it's calculated value.? But since the tube's input C on a pair of 3-500Z's is 16.6 pf,? it's then 200-16.6 pf =? 183.4 pf. ## The fil choke primarily affects the lower bands. On the upper bands it's less of an issue.? ? 9 uh is 1611 ohms of XL @ 28.5 mhz.? ? ? 3.465 pf = 1611 ohms of XC.? ? ?That amounts to dick on 28.5 mhz...and the pair of 3-500Z's still has 16.6 pf...so now it's 16.6 - 3.465 pf = 13.135 pf.? 13.135 pf has to be subtracted from the calculated C value of the tuned input. ? ##? If you are doing say a PI network for a 3CX-3000A7,? wire the relay switched tuned input? into the cathode.....and temp wire a 50 ohm resistor between one cathode lug....and chassis....and also plug the tube into the socket.? With no fil or B+, all voltages off....and TR relays activated, put ur analyzer on the input...and tweak both arco's for each band for 1:1 swr.? ?50 ohm resistor removed.? Apply B+ and fil V.... and test the amp.? ? It will be sorta close, and perhaps some minor C1 + C2 tweaking required.? That depends on drive level, bias used,? loaded B+ used, amp tuned to max PO.... and perhaps loading increased till PO drops 1-2%, and cable length between xcvr and input to amp.? ##? if the relay switched, tuned input board is below the chassis, near the cathode, it may or may not be possible to tweak all the arco caps.? ?The board would have to be mounted to rear apron, with holes to access the caps..or to chassis..pita. If amp is fan cooled, you might be able to remove bottom lid.? If a chimney is used, removal of bottom lid means? zero airflow.?? ? ##? This is why I went to the pair of broadcast caps + tapped coil, manually tuned, tuned input setup on the hb amps.? ? Jim? ?VE7RF |
开云体育So this would be 5?
I have tried 7, 6 and 5 turns.? NO band pass. Only a cut off past 40mhz.
As I remove turns I require less and less cap on each side.??
With this winding it's 0pf on each side.? If I add even 10pf swr raises.??
I am lost now.? Maybe try 8 turns?? ?The instructions say 100pf, 7 turns and 100PF
C
On Jan 15, 2024 9:01 AM, "Mike Feher via groups.io" <n4fs@...> wrote:
If a wire goes through the center of a toroid, it counts and acts as a turn. It does not need to be looped around. 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ? From: [email protected] <[email protected]>
On Behalf Of W7WRX
Sent: Monday, January 15, 2024 10:25 AM To: [email protected] Subject: Re: [ham-amplifiers] Tuned input ? I removed 2 turns and still do not see band pass.? What I see is a high pass at 40mhz.? Below that it's pretty flat down the bands.? ? ? It's supposed to be 7 turns of 20awg.? ? Do the wire ends as they loop over the donut count as a turn? ? C ? On Jan 15, 2024 7:27 AM, "Jim VE7RF via groups.io" <jim.thom@...> wrote: On Mon, Jan 15, 2024 at 12:26 AM, W7WRX wrote:
## I design and run the PI tuned inputs through software every other week...then verify on the bench.? For a overall network Q? of '4'? (input Q = 2....and output Q =2)? ?on 10m,(28.5 mhz) when matching 50 ohms from xcvr to 50 ohm tube input Z....?it should be 223.4 pf? - .22 uh? - 223.4 pf.? ## For an overall network Q of? ? '1.8'? (input Q =.9......and output Q = .9) on 28.5 mhz, it's then 100 pf - .28 uh - 100 pf.? ? ##? if ur caps are only 25-35 pf, then ur Q is through the floor...and the coil has way too much uh.? ? ## either remove a turn or maybe 2, and? / or spread the turns? a bit.? Tweak the coil till both caps are in the 100-140 pf range.? Ok, at that point, you will see the 1:1 swr @ 28.5 mhz..... which should remain flat between? 28.0? and 29,0...then rise when u go below 28 mhz...and above 29 mhz. ? ##? with the Q through the floor, it all goes to hell...and you won't get a? proper bandpass response.? ? ## Have u tested al the other bands yet ?? ? IE: installed caps and toroid's for the other bands...and tested other bands.? ? ##? Note on the above,? only when matching 50 ohms to 50 ohms? (or any 2 x equal Z's)? is the C1 + C2 caps both the same value.? On software, we only tweak the overall network Q.? ?The C1 input Q? ?+ the C2 output Q = overall network Q.? ##? For a PI network for the kw output side, (High tube Z? down to 50 ohms), typ an Overall network Q of....'12' is used....which consist of an input Q of 10...and an output Q of 2.?? ##? In the old ARRL books (and also Eimac's? 'care + feeding'), they only used the INPUT Q...which is why they said? to use a Q of? '10'.? ?They did the same thing with PI tuned inputs.? When they said to use a Q of..'2'? ?what they really meant was to use an overall network Q of 4.? ? ##? For tuned inputs that are tweaked once ..in the middle of the band,? you want low swr? across the entire band.? ?500 khz on 80m is like 1mhz wide on 40m..and 2 mhz wide on 20m..and 4 mhz wide on 10m.? This is where you can do some creative tweaking.?
Each band is different....with 160m only 200 khz? wide, 80m = 500 khz, 40m = 300 khz, 30m = 50 khz,? 20m = 350 khz, 17m = 100 khz, 15m = 450 khz, 12m = 100 khz, 10m = 1700 khz.? ( 6m = 4000 khz). ? ## here is the other thing u gotta worry about.? The tube's input C? is directly in parallel with the C2 of the tuned input. Say a 3CX-3000A7.... with it's 38 pf input C (grid to cathode C).? Now you have to subtract 38 pf from the calculated C2 values of ALL the various tuned inputs for each band.? ##? here's the other thing to deal with.... the XL of the bifilar fil choke (since it's RF grnded at it's cold end...and hot end of fil choke goes to the cathode) is also directly in parallel with the tube's input cathode to grid C.? ##? On a SB-220, they used a 9 uh (per winding) fil choke.? ?XL @ 3.75 mhz =? 212 ohms.? ?You now require 212 ohms of XC to cancel out the XL.? ? 200 pf @ 3.750 mhz = 212 ohms of XC.? On an SB-220, the C2 cap of the 75m tuned input has to be increased by 200 pf? vs it's calculated value.? But since the tube's input C on a pair of 3-500Z's is 16.6 pf,? it's then 200-16.6 pf =? 183.4 pf. ## The fil choke primarily affects the lower bands. On the upper bands it's less of an issue.? ? 9 uh is 1611 ohms of XL @ 28.5 mhz.? ? ? 3.465 pf = 1611 ohms of XC.? ? ?That amounts to dick on 28.5 mhz...and the pair of 3-500Z's still has 16.6 pf...so now it's 16.6 - 3.465 pf = 13.135 pf.? 13.135 pf has to be subtracted from the calculated C value of the tuned input. ? ##? If you are doing say a PI network for a 3CX-3000A7,? wire the relay switched tuned input? into the cathode.....and temp wire a 50 ohm resistor between one cathode lug....and chassis....and also plug the tube into the socket.? With no fil or B+, all voltages off....and TR relays activated, put ur analyzer on the input...and tweak both arco's for each band for 1:1 swr.? ?50 ohm resistor removed.? Apply B+ and fil V.... and test the amp.? ? It will be sorta close, and perhaps some minor C1 + C2 tweaking required.? That depends on drive level, bias used,? loaded B+ used, amp tuned to max PO.... and perhaps loading increased till PO drops 1-2%, and cable length between xcvr and input to amp.? ##? if the relay switched, tuned input board is below the chassis, near the cathode, it may or may not be possible to tweak all the arco caps.? ?The board would have to be mounted to rear apron, with holes to access the caps..or to chassis..pita. If amp is fan cooled, you might be able to remove bottom lid.? If a chimney is used, removal of bottom lid means? zero airflow.?? ? ##? This is why I went to the pair of broadcast caps + tapped coil, manually tuned, tuned input setup on the hb amps.? ? Jim? ?VE7RF |
开云体育Yes,those are? 5 turns. ? A pi-filter with capacitors as shunt elements is a low pass filter, not a band pass filter. ? Differences from the instructions to the real world might be caused by stray and input capacitances which have to be deducted from the theroretical values. ? Just use a non inductive resistor as a load in parallel to the output? and adjust for minimum swr on a VNA or swr meter. ? 73 Peter, DJ7WW ? ? ? -----Original-Nachricht----- Betreff: Re: [ham-amplifiers] Tuned input Datum: 2024-01-15T17:10:46+0100 Von: "W7WRX" <clark@...> An: "[email protected]" <[email protected]> ? ? ? ? So this would be 5?
?
I have tried 7, 6 and 5 turns.? NO band pass. Only a cut off past 40mhz.
?
As I remove turns I require less and less cap on each side.??
?
With this winding it's 0pf on each side.? If I add even 10pf swr raises.??
?
I am lost now.? Maybe try 8 turns?? ?The instructions say 100pf, 7 turns and 100PF
?
C
On Jan 15, 2024 9:01 AM, "Mike Feher via groups.io" <n4fs@...> wrote:
If a wire goes through the center of a toroid, it counts and acts as a turn. It does not need to be looped around. 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ? From: [email protected] <[email protected]> On Behalf Of W7WRX
Sent: Monday, January 15, 2024 10:25 AM To: [email protected] Subject: Re: [ham-amplifiers] Tuned input ? I removed 2 turns and still do not see band pass.? What I see is a high pass at 40mhz.? Below that it's pretty flat down the bands.? ? ? It's supposed to be 7 turns of 20awg.? ? Do the wire ends as they loop over the donut count as a turn? ? C ? On Jan 15, 2024 7:27 AM, "Jim VE7RF via groups.io" <jim.thom@...> wrote: On Mon, Jan 15, 2024 at 12:26 AM, W7WRX wrote:
## I design and run the PI tuned inputs through software every other week...then verify on the bench.? For a overall network Q? of '4'? (input Q = 2....and output Q =2)? ?on 10m,(28.5 mhz) when matching 50 ohms from xcvr to 50 ohm tube input Z....?it should be 223.4 pf? - .22 uh? - 223.4 pf.? ## For an overall network Q of? ? '1.8'? (input Q =.9......and output Q = .9) on 28.5 mhz, it's then 100 pf - .28 uh - 100 pf.? ? ##? if ur caps are only 25-35 pf, then ur Q is through the floor...and the coil has way too much uh.? ? ## either remove a turn or maybe 2, and? / or spread the turns? a bit.? Tweak the coil till both caps are in the 100-140 pf range.? Ok, at that point, you will see the 1:1 swr @ 28.5 mhz..... which should remain flat between? 28.0? and 29,0...then rise when u go below 28 mhz...and above 29 mhz. ? ##? with the Q through the floor, it all goes to hell...and you won't get a? proper bandpass response.? ? ## Have u tested al the other bands yet ?? ? IE: installed caps and toroid's for the other bands...and tested other bands.? ? ##? Note on the above,? only when matching 50 ohms to 50 ohms? (or any 2 x equal Z's)? is the C1 + C2 caps both the same value.? On software, we only tweak the overall network Q.? ?The C1 input Q? ?+ the C2 output Q = overall network Q.? ##? For a PI network for the kw output side, (High tube Z? down to 50 ohms), typ an Overall network Q of....'12' is used....which consist of an input Q of 10...and an output Q of 2.?? ##? In the old ARRL books (and also Eimac's? 'care + feeding'), they only used the INPUT Q...which is why they said? to use a Q of? '10'.? ?They did the same thing with PI tuned inputs.? When they said to use a Q of..'2'? ?what they really meant was to use an overall network Q of 4.? ? ##? For tuned inputs that are tweaked once ..in the middle of the band,? you want low swr? across the entire band.? ?500 khz on 80m is like 1mhz wide on 40m..and 2 mhz wide on 20m..and 4 mhz wide on 10m.? This is where you can do some creative tweaking.? Each band is different....with 160m only 200 khz? wide, 80m = 500 khz, 40m = 300 khz, 30m = 50 khz,? 20m = 350 khz, 17m = 100 khz, 15m = 450 khz, 12m = 100 khz, 10m = 1700 khz.? ( 6m = 4000 khz). ? ## here is the other thing u gotta worry about.? The tube's input C? is directly in parallel with the C2 of the tuned input. Say a 3CX-3000A7.... with it's 38 pf input C (grid to cathode C).? Now you have to subtract 38 pf from the calculated C2 values of ALL the various tuned inputs for each band.? ##? here's the other thing to deal with.... the XL of the bifilar fil choke (since it's RF grnded at it's cold end...and hot end of fil choke goes to the cathode) is also directly in parallel with the tube's input cathode to grid C.? ##? On a SB-220, they used a 9 uh (per winding) fil choke.? ?XL @ 3.75 mhz =? 212 ohms.? ?You now require 212 ohms of XC to cancel out the XL.? ? 200 pf @ 3.750 mhz = 212 ohms of XC.? On an SB-220, the C2 cap of the 75m tuned input has to be increased by 200 pf? vs it's calculated value.? But since the tube's input C on a pair of 3-500Z's is 16.6 pf,? it's then 200-16.6 pf =? 183.4 pf. ## The fil choke primarily affects the lower bands. On the upper bands it's less of an issue.? ? 9 uh is 1611 ohms of XL @ 28.5 mhz.? ? ? 3.465 pf = 1611 ohms of XC.? ? ?That amounts to dick on 28.5 mhz...and the pair of 3-500Z's still has 16.6 pf...so now it's 16.6 - 3.465 pf = 13.135 pf.? 13.135 pf has to be subtracted from the calculated C value of the tuned input. ? ##? If you are doing say a PI network for a 3CX-3000A7,? wire the relay switched tuned input? into the cathode.....and temp wire a 50 ohm resistor between one cathode lug....and chassis....and also plug the tube into the socket.? With no fil or B+, all voltages off....and TR relays activated, put ur analyzer on the input...and tweak both arco's for each band for 1:1 swr.? ?50 ohm resistor removed.? Apply B+ and fil V.... and test the amp.? ? It will be sorta close, and perhaps some minor C1 + C2 tweaking required.? That depends on drive level, bias used,? loaded B+ used, amp tuned to max PO.... and perhaps loading increased till PO drops 1-2%, and cable length between xcvr and input to amp.? ##? if the relay switched, tuned input board is below the chassis, near the cathode, it may or may not be possible to tweak all the arco caps.? ?The board would have to be mounted to rear apron, with holes to access the caps..or to chassis..pita. If amp is fan cooled, you might be able to remove bottom lid.? If a chimney is used, removal of bottom lid means? zero airflow.?? ? ##? This is why I went to the pair of broadcast caps + tapped coil, manually tuned, tuned input setup on the hb amps.? ? Jim? ?VE7RF ? |
开云体育Yes, a real easy way to tell is to look at the transfer function with omega equal 0. A non mathematical way is simply, if you put DC in will you get DC out? 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ? From: [email protected] <[email protected]> On Behalf Of Peter Voelpel
Sent: Monday, January 15, 2024 11:45 AM To: [email protected] Subject: Re: [ham-amplifiers] Tuned input ? Yes,those are? 5 turns. ? A pi-filter with capacitors as shunt elements is a low pass filter, not a band pass filter. ? Differences from the instructions to the real world might be caused by stray and input capacitances which have to be deducted from the theroretical values. ? Just use a non inductive resistor as a load in parallel to the output? and adjust for minimum swr on a VNA or swr meter. ? 73 Peter, DJ7WW ? ? ? -----Original-Nachricht----- Betreff: Re: [ham-amplifiers] Tuned input Datum: 2024-01-15T17:10:46+0100 Von: "W7WRX" <clark@...> An: "[email protected]" <[email protected]> ? ? ? ? So this would be 5? ? I have tried 7, 6 and 5 turns.? NO band pass. Only a cut off past 40mhz. ? As I remove turns I require less and less cap on each side.?? ? With this winding it's 0pf on each side.? If I add even 10pf swr raises.?? ? I am lost now.? Maybe try 8 turns?? ?The instructions say 100pf, 7 turns and 100PF ? C ? On Jan 15, 2024 9:01 AM, "Mike Feher via groups.io" <n4fs@...> wrote: If a wire goes through the center of a toroid, it counts and acts as a turn. It does not need to be looped around. 73 – Mike ? Mike B. Feher, N4FS 89 Arnold Blvd. Howell NJ 07731 848-245-9115 ? From: [email protected] <[email protected]> On Behalf Of W7WRX ? I removed 2 turns and still do not see band pass.? What I see is a high pass at 40mhz.? Below that it's pretty flat down the bands.? ? ? It's supposed to be 7 turns of 20awg.? ? Do the wire ends as they loop over the donut count as a turn? ? C ? On Jan 15, 2024 7:27 AM, "Jim VE7RF via groups.io" <jim.thom@...> wrote: On Mon, Jan 15, 2024 at 12:26 AM, W7WRX wrote:
## I design and run the PI tuned inputs through software every other week...then verify on the bench.? For a overall network Q? of '4'? (input Q = 2....and output Q =2)? ?on 10m,(28.5 mhz) when matching 50 ohms from xcvr to 50 ohm tube input Z....?it should be 223.4 pf? - .22 uh? - 223.4 pf.? ## For an overall network Q of? ? '1.8'? (input Q =.9......and output Q = .9) on 28.5 mhz, it's then 100 pf - .28 uh - 100 pf.? ? ##? if ur caps are only 25-35 pf, then ur Q is through the floor...and the coil has way too much uh.? ? ## either remove a turn or maybe 2, and? / or spread the turns? a bit.? Tweak the coil till both caps are in the 100-140 pf range.? Ok, at that point, you will see the 1:1 swr @ 28.5 mhz..... which should remain flat between? 28.0? and 29,0...then rise when u go below 28 mhz...and above 29 mhz. ? ##? with the Q through the floor, it all goes to hell...and you won't get a? proper bandpass response.? ? ## Have u tested al the other bands yet ?? ? IE: installed caps and toroid's for the other bands...and tested other bands.? ? ##? Note on the above,? only when matching 50 ohms to 50 ohms? (or any 2 x equal Z's)? is the C1 + C2 caps both the same value.? On software, we only tweak the overall network Q.? ?The C1 input Q? ?+ the C2 output Q = overall network Q.? ##? For a PI network for the kw output side, (High tube Z? down to 50 ohms), typ an Overall network Q of....'12' is used....which consist of an input Q of 10...and an output Q of 2.?? ##? In the old ARRL books (and also Eimac's? 'care + feeding'), they only used the INPUT Q...which is why they said? to use a Q of? '10'.? ?They did the same thing with PI tuned inputs.? When they said to use a Q of..'2'? ?what they really meant was to use an overall network Q of 4.? ? ##? For tuned inputs that are tweaked once ..in the middle of the band,? you want low swr? across the entire band.? ?500 khz on 80m is like 1mhz wide on 40m..and 2 mhz wide on 20m..and 4 mhz wide on 10m.? This is where you can do some creative tweaking.? Each band is different....with 160m only 200 khz? wide, 80m = 500 khz, 40m = 300 khz, 30m = 50 khz,? 20m = 350 khz, 17m = 100 khz, 15m = 450 khz, 12m = 100 khz, 10m = 1700 khz.? ( 6m = 4000 khz). ? ## here is the other thing u gotta worry about.? The tube's input C? is directly in parallel with the C2 of the tuned input. Say a 3CX-3000A7.... with it's 38 pf input C (grid to cathode C).? Now you have to subtract 38 pf from the calculated C2 values of ALL the various tuned inputs for each band.? ##? here's the other thing to deal with.... the XL of the bifilar fil choke (since it's RF grnded at it's cold end...and hot end of fil choke goes to the cathode) is also directly in parallel with the tube's input cathode to grid C.? ##? On a SB-220, they used a 9 uh (per winding) fil choke.? ?XL @ 3.75 mhz =? 212 ohms.? ?You now require 212 ohms of XC to cancel out the XL.? ? 200 pf @ 3.750 mhz = 212 ohms of XC.? On an SB-220, the C2 cap of the 75m tuned input has to be increased by 200 pf? vs it's calculated value.? But since the tube's input C on a pair of 3-500Z's is 16.6 pf,? it's then 200-16.6 pf =? 183.4 pf. ## The fil choke primarily affects the lower bands. On the upper bands it's less of an issue.? ? 9 uh is 1611 ohms of XL @ 28.5 mhz.? ? ? 3.465 pf = 1611 ohms of XC.? ? ?That amounts to dick on 28.5 mhz...and the pair of 3-500Z's still has 16.6 pf...so now it's 16.6 - 3.465 pf = 13.135 pf.? 13.135 pf has to be subtracted from the calculated C value of the tuned input. ? ##? If you are doing say a PI network for a 3CX-3000A7,? wire the relay switched tuned input? into the cathode.....and temp wire a 50 ohm resistor between one cathode lug....and chassis....and also plug the tube into the socket.? With no fil or B+, all voltages off....and TR relays activated, put ur analyzer on the input...and tweak both arco's for each band for 1:1 swr.? ?50 ohm resistor removed.? Apply B+ and fil V.... and test the amp.? ? It will be sorta close, and perhaps some minor C1 + C2 tweaking required.? That depends on drive level, bias used,? loaded B+ used, amp tuned to max PO.... and perhaps loading increased till PO drops 1-2%, and cable length between xcvr and input to amp.? ##? if the relay switched, tuned input board is below the chassis, near the cathode, it may or may not be possible to tweak all the arco caps.? ?The board would have to be mounted to rear apron, with holes to access the caps..or to chassis..pita. If amp is fan cooled, you might be able to remove bottom lid.? If a chimney is used, removal of bottom lid means? zero airflow.?? ? ##? This is why I went to the pair of broadcast caps + tapped coil, manually tuned, tuned input setup on the hb amps.? ? Jim? ?VE7RF ? ? |
|
Peter.??
This is NOT a band pass filter?? I am confused here.? I expected each band slot to have a band pass for that band and a cut off above and below. What I see is that I can adjust the match to 1.0 to 1.0 at near 50 ohms.? But the band pass is only a cut off ABOVE the primary. Example: 10 meters.? ?Low SWR from 1.8 to 40MHZ.? past 40 it shoots up. 40 meters,? Low SWR from 1.8 to 18 MHZ, Past that it shoots up. Is this expected behavior??? C |
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I don't get it.? Sure, the PI network is a LP filter.? BUT when tweaked for? 1:1? swr at the middle of a band, the swr rises when u go below / above the band edges.? I'm gonna re-check this in the next 2 days...and on a bunch of bands.?? ? On a side note, per JI's? tuned input writeup, the function of the PI filter is to kill harmonics at the cathode from going BACKWARDS towards the xcvr.? In that case, the PI filter has to have LOW Z on all the harmonic freqs.? "An RF power amplifier's tuned input circuit is more than just impedance matching. While reasonable impedance matching can be important for proper exciter operation, the tuned input circuit of a grounded-grid or cathode driven radio frequency power amplifier provides multiple important functions for the amplifier:
A tuner between the amplifier and radio,? a matching circuit some distance from the cathode, or a high pass or broadband network will NOT do all of the above." "Harmonics Current in the CATHODE shares the SAME path through the tube as current in the anode, with an additional current that flows in the grid-cathode path in class sub-2 amplifiers. (AB1?amplifiers have no grid current, while AB2?amplifiers have grid current.) The cathode of a vacuum tube essentially contains the same time-varying current as the anode, and if there is ANY grid current that additional current is also harmonic-rich current." ? "Input Impedance The driving impedance of a cathode driven amplifier always varies some amount with power level and tuning. We can say the input impedance of a cathode driven stage is?dynamic, with the tube's driving impedance changing with parameters like drive power and how the amplifier is loaded or tuned. The input impedance changes dynamically because the output system is in SERIES with the input system. The SAME plate current flows through both cathode and anode systems. Varying anode load impedance, because the same very same current flows through both, CHANGES the input impedance. In general the lower tube mu, the greater the effect of output tuning and power level on driving impedance. This is because a low-mu tube generally has a high driving impedance, making cathode impedance a larger percentage of anode impedance.?The higher cathode impedance increases negative feedback, and increased negative feedback causes the input impedance to vary more with anode load impedance changes. The tuned input's resonance or "flywheel effect" does not stabilize this impedance variation, but additional losses brought into the cathode system by tuned input circuit components helps dilute or "swamp out" dynamic changes in driving impedance. An attenuator pad would do the same of course, but would not filter harmonics or sharpen conduction point transitions. The dynamic cathode impedance, where cathode impedance changes with drive level, PREVENTS? us from accurately adjusting the tuned input system of a typical cathode driven amplifier at very low power. This prevents accurate use of an antenna analyzer to adjust the tuned input while using the operating PA tube as a load. The input system should always be adjusted near full output power under normal operating conditions, or with a suitable dummy load replacing the tube's dynamic impedance. A reasonable approximation of tube input impedance, for circuit adjustment purposes, would be a small non-inductive resistor from each cathode pin to a control grid pin at each tube. This resistor should be the approximate value of the tube input resistance when driven near full power with normal tuning and loading. Filament power and HV should be off and the tubes left in place, and the input driven normally as if the amplifier was running but with a low power antenna analyzer substituting for the the normal exciter. ? |
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One added note for LP filters....like used on the output of SS amps.? The harmonics don't get absorbed by the LP filter, nor are they routed to grnd.? ?They get reflected by towards the final PA. The LP filter looks like a HIGH Z to harmonics ABOVE? the LP filter cut off freq.? That's why Flex used a diplexer on it's PGXL.? ?Each high power rated LP filter has a mating low power HP filter...( input of each is bonded).? Harmonics from the HP filter are routed to a 400 watt DL.? In the old ARRL books, they called that a ...' absorption typ LP filter'.? That combo of LP + HP filter is not as easy as it looks.? ?When the inputs of both filters are bonded..... they filters interact with each other, screwing up the response of the LP filter..... which then requires some re-tweaking of the coils. In the case of the LP filter on the PI tuned input for the GG / cathode driven amp....the harmonics are generated at the cathode....and will feed backwards toward the xcvr.? In this case, the PI tuned input is a LP filter, but with harmonics being? The other somewhat semi popular tuned input is the T filter....which consist of 2 x coils in series, with a cap from the junction point to chassis.? It too is a LP filter...BUT when used as a tuned input, will not present a high Z to harmonics being generated at the cathode...and being fed backwards to the xcvr.?? ? We dumped the idea of a T? tuned input on that 6m 10 kw amp....and went with a conventional PI tuned input.? It's manually tuned, with 2 x air caps and one coil.......and covers the entire 50-54 mhz.? ? None of this explains why Clarks tuned input board is screwed up.? |
开云体育I ran the board into a dummy load with an FT450.? It shows flat with relay off in pass through.? Engaged it shows 1.0 with Trimmers at zero.
?Any attempt to adjust the caps from zero raises SWR.? Even added ladders and adjusted all the way to 1200pf.? It only raises SWR and rig cuts back.
I then ran the board into a 2 to 1 load.? ?It shows 2 to 1 on xcvr meter in pass through and with zero trimmer.
Any attempt to dial Trimmers up increases SWR.
Obviously the toroid is wrong.? I am told you can't stick a toroid Into an LCR. You will get a false reading.? You must use a grid dip or, a sig generator, scope and a known cap to resonate it.? Then you can find out where it dips and then work
backwards to the L of the toroid.
On Jan 16, 2024 9:17 AM, "Jim VE7RF via groups.io" <jim.thom@...> wrote:
One added note for LP filters....like used on the output of SS amps.? The harmonics don't get absorbed by the LP filter, nor are they routed to grnd.? ?They get reflected by towards the final PA. The LP filter looks like a HIGH Z to harmonics ABOVE? the LP filter cut off freq.? That's why Flex used a diplexer on it's PGXL.? ?Each high power rated LP filter has a mating low power HP filter...( input of each is bonded).? Harmonics from the HP filter are routed to a 400 watt DL.? In the old ARRL books, they called that a ...' absorption typ LP filter'.? That combo of LP + HP filter is not as easy as it looks.? ?When the inputs of both filters are bonded..... they filters interact with each other, screwing up the response of the LP filter..... which then requires some re-tweaking of the coils. In the case of the LP filter on the PI tuned input for the GG / cathode driven amp....the harmonics are generated at the cathode....and will feed backwards toward the xcvr.? In this case, the PI tuned input is a LP filter, but with harmonics being? The other somewhat semi popular tuned input is the T filter....which consist of 2 x coils in series, with a cap from the junction point to chassis.? It too is a LP filter...BUT when used as a tuned input, will not present a high Z to harmonics being generated at the cathode...and being fed backwards to the xcvr.?? ? We dumped the idea of a T? tuned input on that 6m 10 kw amp....and went with a conventional PI tuned input.? It's manually tuned, with 2 x air caps and one coil.......and covers the entire 50-54 mhz.? ? None of this explains why Clarks tuned input board is screwed up.? |
