On Jan 24, 2024, at 2:31 PM, Rich k0zx <k0zx.co@...> wrote:

?Here is what Ameritron has replaced that part number with today (attached):

<varcap.JPG>

On Jan 24, 2024, at 2:05 PM, Rich k0zx <k0zx.co@...> wrote:

?Spoke with rob, found in catalog, but unfortunately this cap is significantly lower voltage rating than the 3.5kv needed in these amp supply boxes. Also plate count different, so it most likely closer plates and so lower voltage rating. Perfect for the AL-xxxs but looks like not prime time for this radio. Rebuilding if I can get the plates is ok here, no mods needed if find. But tnx for the leads
rich

On Jan 23, 2024, at 11:13 PM, W7WRX <clark@...> wrote:

?

Not paul.

Attached is the page in service manual.? They want you to Preset both coils.

They revised the values of the tune and load door knobs per band.? It's very different from early and mid models.?

They also changed the solenoids/relays for those door knobs.? Mine has the later thicker plate devices. They look mint.

The amp will be used for DXing at pretty low power.? The big advantage for me is the 16 presets.? I can simply turn a knob, make a contact and jump bands.? Don't care if it makes slot of power.? Would blow up my mosley anyways.?

The fact that this thing has a horrible input match just annoyed me so I will fix that and it should be good to go.

C

On Jan 23, 2024 7:48 PM, "Amp Guy Llc via groups.io" <kb1sel@...> wrote:

But you said the coil alignment procedure is in the manual , I must have missed it. Do you know the page number.?

Once the pa is working , I strongly suggest selling. Take the money and run

You talking about Paul ?

Some guys change the cap values to shift the resonance point on the l1 and l2 coils, after they have put a pit in the coil or the shaft the wheel rides on. So the wheel ends up in a different spot on shaft and coil.?

The c1 fixed ceramic doorknob caps love to arc to the chassis and to the shorting flappers in the middle which are at ground potential. Turns into a real mess. The microy material is fun to obtain and then have machined.?

Amp guy llc

Amprepairguy.com

YouTube Amp repair guy

203-892-4119

On Jan 23, 2024, at 8:26 PM, W7WRX <clark@...> wrote:

?

Mine is the latest version.? I am friends eith the engineer that revised the tank and door knobs to gain efficiency on 8k.? We face timed and had the covers off his amp and mine and compared them.??

I think Jim must be talking about something else.? No way in hell an ameritron AL 1200 or 1500 does 50 db down. The manual shows -34 BEST case on best band.??

I got my 2 tone setup now and ran the radio to verify.? I will two tone the 8k and see what it shows. I wanted this data before adding the input.? I was using a carrier prior and just looking at the spec an lightly coupled. No attenuator.??

In any case the tuned input board reduces the harmonics by at least 20DB and can be as much as 30.?

Now Jim, what the heck are you talking about brother?? How are you testing to get -50 out of an ameritron?? ?You certainly can't be talking about IMD????? Confused...

C

On Jan 23, 2024 4:02 PM, "Amp Guy Llc via groups.io" <kb1sel@...> wrote:

On what page of the manual does the book show alignment of the inductors . Ted Henry nor anyone worse I talked to at Henry radio had any clue, ?10 plus years ago . Also had no records of revisions ?they had done.?

I was rebuilding / fixing for re sale?

Ka1cde pat , was nice enough to let me come up to see his , to copy . As his was one of the last ones made , and was the most current version with all updates.?

Amp guy llc

Amprepairguy.com

YouTube Amp repair guy

203-892-4119

On Jan 23, 2024, at 12:21 PM, W7WRX <clark@...> wrote:

?

The board has a pass-through trace if no relays are selected.? RF in and OUT.? As you select a single relay, it pulls the contacts off the jump trace and places the inductor in series.? The caps go to ground. Simple.

I was just testing the board into the amp. I understand that it will be different once installed and that Unun mess is removed.

I read online that you should use the .01 coupling cap when making your bench settings.?

I tried this and found no difference on any band.? ?There is a page online where a man shows how the coupling cap effects it with graphs. I think he had something else going on.?

Its very hard to believe the -50 figure.? That seems out of the range of reality.? ?I have measured dozens and dozens of amps here and most are -29 to -32 DB range using a radio that is -45? The only two amps that are better are my 4cx10000D, which is showing -60DB down as good as the rig and my Collins 30S1 which shows in the -45 range.?

Remember, I was NOT using a Two-tone generator for my tests that I posted for the 8K. I was simply using a RTTY carrier with the Spec An loosely coupled.? ?

I was just trying to see if the board was in fact working on all bands and trying to see how much its going to lower harmonics as I tuned each band.

I also wanted to see if the inductors would heat with a 100W RTTY carrier through them. They dont.? They run cool and imagine how much air will be on the board near the tube socket.

Once I install the board, I can run a two-tone proper test and see how the overall amp performs.? It's dirty now. Real dirty.??

One thing I will circle back on is the adjustment of the LOAD side inductor in the 8k ultra.? ?Peter got me thinking.

The book shows how to align the big roller and the load side roller.? I was told by a man that worked for Henry on the 8k to adjust the load coil for max output.??

To do this you tune the amp on 20 meters,? Derail the chain and manually adjust the Load inductor for max output.? I did this with a tuning pulser and found 1000w!!! more output.? ?

I am now thinking of resetting it and testing the harmonics again to see if this throws off the network.??

Unfortunately, I was in the hospital over new year's and they found a herniated disk in my back, A growth on one disk and a problem in with my SI on left side.? I have been in massive pain and started physical therapy.? I don't think it's a good idea that I pull that RF deck right now. I am going to have to wait a bit and get a friend over here to help me yank it!?

C

---

From: [email protected] <[email protected]> on behalf of Jim VE7RF via groups.io <jim.thom@...>
Sent: Tuesday, January 23, 2024 7:25 AM
To: [email protected] <[email protected]>
Subject: Re: [ham-amplifiers] Tuned input

?

Clark, does the tuned input board have some sort of bypass mode ??? ? It would require one extra relay to pull that off.?
With relays wired correctly, only one relay is ever energized....(for whatever band it's on).? ?With no relays energized, the xcvr should see a wide open.? ?

?

If the output of the tuned input board is feeding that back to back un-un mess, that could easily screw things up.? You might want to at least temp bypass the 3 x un-uns and the relay that switches the back to back un-uns to the single un-un. Then retweak the Arco's.? If all is well, then remove the mess of un-uns + their relay.? Then feed the output of the tuned inputs....to the cathode..via the oem henry 4 x paralleled? .01uf coupling caps.?
A .01 uf coupling cap should not affect the tuning.? .01uf = 10,000 pf? =? 8.84 ohms of XL @ 1.8 mhz? = dick, non issue.? ?4 x .01uf caps in parallel = 40,000 pf =? 2.21 ohms of XC @ 1.8 mhz? = less than dick.?

Typ kw PI network on the output side is down 50 db for 2nd harmonic suppression.....and even more with a PI-L.? With the un-un mess bypassed / removed, you will probably see a big improvement.?

In the high gloss? Eimac catalog, they state IMD3 for the 3CX-3000A7? is -53dbc (-59db pep)...and that's at 5 kw pep out, using their 2 tone test.? ? It's one of the cleanest tubes in the entire catalog.?

Jim? ?VE7RF

<20240123_210646.jpg>

On Jan 23, 2024, at 8:26 PM, W7WRX <clark@...> wrote:

?

Mine is the latest version.? I am friends eith the engineer that revised the tank and door knobs to gain efficiency on 8k.? We face timed and had the covers off his amp and mine and compared them.??

I think Jim must be talking about something else.? No way in hell an ameritron AL 1200 or 1500 does 50 db down. The manual shows -34 BEST case on best band.??

I got my 2 tone setup now and ran the radio to verify.? I will two tone the 8k and see what it shows. I wanted this data before adding the input.? I was using a carrier prior and just looking at the spec an lightly coupled. No attenuator.??

In any case the tuned input board reduces the harmonics by at least 20DB and can be as much as 30.?

Now Jim, what the heck are you talking about brother?? How are you testing to get -50 out of an ameritron?? ?You certainly can't be talking about IMD????? Confused...

C

On Jan 23, 2024 4:02 PM, "Amp Guy Llc via groups.io" <kb1sel@...> wrote:

On what page of the manual does the book show alignment of the inductors . Ted Henry nor anyone worse I talked to at Henry radio had any clue, ?10 plus years ago . Also had no records of revisions ?they had done.?

I was rebuilding / fixing for re sale?

Ka1cde pat , was nice enough to let me come up to see his , to copy . As his was one of the last ones made , and was the most current version with all updates.?

Amp guy llc

Amprepairguy.com

YouTube Amp repair guy

203-892-4119

On Jan 23, 2024, at 12:21 PM, W7WRX <clark@...> wrote:

?

The board has a pass-through trace if no relays are selected.? RF in and OUT.? As you select a single relay, it pulls the contacts off the jump trace and places the inductor in series.? The caps go to ground. Simple.

I was just testing the board into the amp. I understand that it will be different once installed and that Unun mess is removed.

I read online that you should use the .01 coupling cap when making your bench settings.?

I tried this and found no difference on any band.? ?There is a page online where a man shows how the coupling cap effects it with graphs. I think he had something else going on.?

Its very hard to believe the -50 figure.? That seems out of the range of reality.? ?I have measured dozens and dozens of amps here and most are -29 to -32 DB range using a radio that is -45? The only two amps that are better are my 4cx10000D, which is showing -60DB down as good as the rig and my Collins 30S1 which shows in the -45 range.?

Remember, I was NOT using a Two-tone generator for my tests that I posted for the 8K. I was simply using a RTTY carrier with the Spec An loosely coupled.? ?

I was just trying to see if the board was in fact working on all bands and trying to see how much its going to lower harmonics as I tuned each band.

I also wanted to see if the inductors would heat with a 100W RTTY carrier through them. They dont.? They run cool and imagine how much air will be on the board near the tube socket.

Once I install the board, I can run a two-tone proper test and see how the overall amp performs.? It's dirty now. Real dirty.??

One thing I will circle back on is the adjustment of the LOAD side inductor in the 8k ultra.? ?Peter got me thinking.

The book shows how to align the big roller and the load side roller.? I was told by a man that worked for Henry on the 8k to adjust the load coil for max output.??

To do this you tune the amp on 20 meters,? Derail the chain and manually adjust the Load inductor for max output.? I did this with a tuning pulser and found 1000w!!! more output.? ?

I am now thinking of resetting it and testing the harmonics again to see if this throws off the network.??

Unfortunately, I was in the hospital over new year's and they found a herniated disk in my back, A growth on one disk and a problem in with my SI on left side.? I have been in massive pain and started physical therapy.? I don't think it's a good idea that I pull that RF deck right now. I am going to have to wait a bit and get a friend over here to help me yank it!?

C

---

From: [email protected] <[email protected]> on behalf of Jim VE7RF via groups.io <jim.thom@...>
Sent: Tuesday, January 23, 2024 7:25 AM
To: [email protected] <[email protected]>
Subject: Re: [ham-amplifiers] Tuned input

?

Clark, does the tuned input board have some sort of bypass mode ??? ? It would require one extra relay to pull that off.?
With relays wired correctly, only one relay is ever energized....(for whatever band it's on).? ?With no relays energized, the xcvr should see a wide open.? ?

?

If the output of the tuned input board is feeding that back to back un-un mess, that could easily screw things up.? You might want to at least temp bypass the 3 x un-uns and the relay that switches the back to back un-uns to the single un-un. Then retweak the Arco's.? If all is well, then remove the mess of un-uns + their relay.? Then feed the output of the tuned inputs....to the cathode..via the oem henry 4 x paralleled? .01uf coupling caps.?
A .01 uf coupling cap should not affect the tuning.? .01uf = 10,000 pf? =? 8.84 ohms of XL @ 1.8 mhz? = dick, non issue.? ?4 x .01uf caps in parallel = 40,000 pf =? 2.21 ohms of XC @ 1.8 mhz? = less than dick.?

Typ kw PI network on the output side is down 50 db for 2nd harmonic suppression.....and even more with a PI-L.? With the un-un mess bypassed / removed, you will probably see a big improvement.?

In the high gloss? Eimac catalog, they state IMD3 for the 3CX-3000A7? is -53dbc (-59db pep)...and that's at 5 kw pep out, using their 2 tone test.? ? It's one of the cleanest tubes in the entire catalog.?

Jim? ?VE7RF

On Jan 23, 2024, at 8:26 PM, W7WRX <clark@...> wrote:

?

Mine is the latest version.? I am friends eith the engineer that revised the tank and door knobs to gain efficiency on 8k.? We face timed and had the covers off his amp and mine and compared them.??

I think Jim must be talking about something else.? No way in hell an ameritron AL 1200 or 1500 does 50 db down. The manual shows -34 BEST case on best band.??

I got my 2 tone setup now and ran the radio to verify.? I will two tone the 8k and see what it shows. I wanted this data before adding the input.? I was using a carrier prior and just looking at the spec an lightly coupled. No attenuator.??

In any case the tuned input board reduces the harmonics by at least 20DB and can be as much as 30.?

Now Jim, what the heck are you talking about brother?? How are you testing to get -50 out of an ameritron?? ?You certainly can't be talking about IMD????? Confused...

C

On Jan 23, 2024 4:02 PM, "Amp Guy Llc via groups.io" <kb1sel@...> wrote:

On what page of the manual does the book show alignment of the inductors . Ted Henry nor anyone worse I talked to at Henry radio had any clue, ?10 plus years ago . Also had no records of revisions ?they had done.?

I was rebuilding / fixing for re sale?

Ka1cde pat , was nice enough to let me come up to see his , to copy . As his was one of the last ones made , and was the most current version with all updates.?

Amp guy llc

Amprepairguy.com

YouTube Amp repair guy

203-892-4119

On Jan 23, 2024, at 12:21 PM, W7WRX <clark@...> wrote:

?

The board has a pass-through trace if no relays are selected.? RF in and OUT.? As you select a single relay, it pulls the contacts off the jump trace and places the inductor in series.? The caps go to ground. Simple.

I was just testing the board into the amp. I understand that it will be different once installed and that Unun mess is removed.

I read online that you should use the .01 coupling cap when making your bench settings.?

I tried this and found no difference on any band.? ?There is a page online where a man shows how the coupling cap effects it with graphs. I think he had something else going on.?

Its very hard to believe the -50 figure.? That seems out of the range of reality.? ?I have measured dozens and dozens of amps here and most are -29 to -32 DB range using a radio that is -45? The only two amps that are better are my 4cx10000D, which is showing -60DB down as good as the rig and my Collins 30S1 which shows in the -45 range.?

Remember, I was NOT using a Two-tone generator for my tests that I posted for the 8K. I was simply using a RTTY carrier with the Spec An loosely coupled.? ?

I was just trying to see if the board was in fact working on all bands and trying to see how much its going to lower harmonics as I tuned each band.

I also wanted to see if the inductors would heat with a 100W RTTY carrier through them. They dont.? They run cool and imagine how much air will be on the board near the tube socket.

Once I install the board, I can run a two-tone proper test and see how the overall amp performs.? It's dirty now. Real dirty.??

One thing I will circle back on is the adjustment of the LOAD side inductor in the 8k ultra.? ?Peter got me thinking.

The book shows how to align the big roller and the load side roller.? I was told by a man that worked for Henry on the 8k to adjust the load coil for max output.??

To do this you tune the amp on 20 meters,? Derail the chain and manually adjust the Load inductor for max output.? I did this with a tuning pulser and found 1000w!!! more output.? ?

I am now thinking of resetting it and testing the harmonics again to see if this throws off the network.??

Unfortunately, I was in the hospital over new year's and they found a herniated disk in my back, A growth on one disk and a problem in with my SI on left side.? I have been in massive pain and started physical therapy.? I don't think it's a good idea that I pull that RF deck right now. I am going to have to wait a bit and get a friend over here to help me yank it!?

C

---

From: [email protected] <[email protected]> on behalf of Jim VE7RF via groups.io <jim.thom@...>
Sent: Tuesday, January 23, 2024 7:25 AM
To: [email protected] <[email protected]>
Subject: Re: [ham-amplifiers] Tuned input

?

Clark, does the tuned input board have some sort of bypass mode ??? ? It would require one extra relay to pull that off.?
With relays wired correctly, only one relay is ever energized....(for whatever band it's on).? ?With no relays energized, the xcvr should see a wide open.? ?

?

If the output of the tuned input board is feeding that back to back un-un mess, that could easily screw things up.? You might want to at least temp bypass the 3 x un-uns and the relay that switches the back to back un-uns to the single un-un. Then retweak the Arco's.? If all is well, then remove the mess of un-uns + their relay.? Then feed the output of the tuned inputs....to the cathode..via the oem henry 4 x paralleled? .01uf coupling caps.?
A .01 uf coupling cap should not affect the tuning.? .01uf = 10,000 pf? =? 8.84 ohms of XL @ 1.8 mhz? = dick, non issue.? ?4 x .01uf caps in parallel = 40,000 pf =? 2.21 ohms of XC @ 1.8 mhz? = less than dick.?

Typ kw PI network on the output side is down 50 db for 2nd harmonic suppression.....and even more with a PI-L.? With the un-un mess bypassed / removed, you will probably see a big improvement.?

In the high gloss? Eimac catalog, they state IMD3 for the 3CX-3000A7? is -53dbc (-59db pep)...and that's at 5 kw pep out, using their 2 tone test.? ? It's one of the cleanest tubes in the entire catalog.?

Jim? ?VE7RF

On Jan 23, 2024, at 12:21 PM, W7WRX <clark@...> wrote:

?

The board has a pass-through trace if no relays are selected.? RF in and OUT.? As you select a single relay, it pulls the contacts off the jump trace and places the inductor in series.? The caps go to ground. Simple.

I was just testing the board into the amp. I understand that it will be different once installed and that Unun mess is removed.

I read online that you should use the .01 coupling cap when making your bench settings.?

I tried this and found no difference on any band.? ?There is a page online where a man shows how the coupling cap effects it with graphs. I think he had something else going on.?

Its very hard to believe the -50 figure.? That seems out of the range of reality.? ?I have measured dozens and dozens of amps here and most are -29 to -32 DB range using a radio that is -45? The only two amps that are better are my 4cx10000D, which is showing -60DB down as good as the rig and my Collins 30S1 which shows in the -45 range.?

Remember, I was NOT using a Two-tone generator for my tests that I posted for the 8K. I was simply using a RTTY carrier with the Spec An loosely coupled.? ?

I was just trying to see if the board was in fact working on all bands and trying to see how much its going to lower harmonics as I tuned each band.

I also wanted to see if the inductors would heat with a 100W RTTY carrier through them. They dont.? They run cool and imagine how much air will be on the board near the tube socket.

Once I install the board, I can run a two-tone proper test and see how the overall amp performs.? It's dirty now. Real dirty.??

One thing I will circle back on is the adjustment of the LOAD side inductor in the 8k ultra.? ?Peter got me thinking.

The book shows how to align the big roller and the load side roller.? I was told by a man that worked for Henry on the 8k to adjust the load coil for max output.??

To do this you tune the amp on 20 meters,? Derail the chain and manually adjust the Load inductor for max output.? I did this with a tuning pulser and found 1000w!!! more output.? ?

I am now thinking of resetting it and testing the harmonics again to see if this throws off the network.??

Unfortunately, I was in the hospital over new year's and they found a herniated disk in my back, A growth on one disk and a problem in with my SI on left side.? I have been in massive pain and started physical therapy.? I don't think it's a good idea that I pull that RF deck right now. I am going to have to wait a bit and get a friend over here to help me yank it!?

C

---

From: [email protected] <[email protected]> on behalf of Jim VE7RF via groups.io <jim.thom@...>
Sent: Tuesday, January 23, 2024 7:25 AM
To: [email protected] <[email protected]>
Subject: Re: [ham-amplifiers] Tuned input

?

Clark, does the tuned input board have some sort of bypass mode ??? ? It would require one extra relay to pull that off.?
With relays wired correctly, only one relay is ever energized....(for whatever band it's on).? ?With no relays energized, the xcvr should see a wide open.? ?

?

If the output of the tuned input board is feeding that back to back un-un mess, that could easily screw things up.? You might want to at least temp bypass the 3 x un-uns and the relay that switches the back to back un-uns to the single un-un. Then retweak the Arco's.? If all is well, then remove the mess of un-uns + their relay.? Then feed the output of the tuned inputs....to the cathode..via the oem henry 4 x paralleled? .01uf coupling caps.?
A .01 uf coupling cap should not affect the tuning.? .01uf = 10,000 pf? =? 8.84 ohms of XL @ 1.8 mhz? = dick, non issue.? ?4 x .01uf caps in parallel = 40,000 pf =? 2.21 ohms of XC @ 1.8 mhz? = less than dick.?

Typ kw PI network on the output side is down 50 db for 2nd harmonic suppression.....and even more with a PI-L.? With the un-un mess bypassed / removed, you will probably see a big improvement.?

In the high gloss? Eimac catalog, they state IMD3 for the 3CX-3000A7? is -53dbc (-59db pep)...and that's at 5 kw pep out, using their 2 tone test.? ? It's one of the cleanest tubes in the entire catalog.?

Jim? ?VE7RF

On Jan 23, 2024, at 6:02 PM, Amp Guy Llc <kb1sel@...> wrote:

?On what page of the manual does the book show alignment of the inductors . Ted Henry nor anyone worse I talked to at Henry radio had any clue, ?10 plus years ago . Also had no records of revisions ?they had done.?

I was rebuilding / fixing for re sale?

Ka1cde pat , was nice enough to let me come up to see his , to copy . As his was one of the last ones made , and was the most current version with all updates.?

Amp guy llc

Amprepairguy.com

YouTube Amp repair guy

203-892-4119

On Jan 23, 2024, at 12:21 PM, W7WRX <clark@...> wrote:

?

The board has a pass-through trace if no relays are selected.? RF in and OUT.? As you select a single relay, it pulls the contacts off the jump trace and places the inductor in series.? The caps go to ground. Simple.

I was just testing the board into the amp. I understand that it will be different once installed and that Unun mess is removed.

I read online that you should use the .01 coupling cap when making your bench settings.?

I tried this and found no difference on any band.? ?There is a page online where a man shows how the coupling cap effects it with graphs. I think he had something else going on.?

Its very hard to believe the -50 figure.? That seems out of the range of reality.? ?I have measured dozens and dozens of amps here and most are -29 to -32 DB range using a radio that is -45? The only two amps that are better are my 4cx10000D, which is showing -60DB down as good as the rig and my Collins 30S1 which shows in the -45 range.?

Remember, I was NOT using a Two-tone generator for my tests that I posted for the 8K. I was simply using a RTTY carrier with the Spec An loosely coupled.? ?

I was just trying to see if the board was in fact working on all bands and trying to see how much its going to lower harmonics as I tuned each band.

I also wanted to see if the inductors would heat with a 100W RTTY carrier through them. They dont.? They run cool and imagine how much air will be on the board near the tube socket.

Once I install the board, I can run a two-tone proper test and see how the overall amp performs.? It's dirty now. Real dirty.??

One thing I will circle back on is the adjustment of the LOAD side inductor in the 8k ultra.? ?Peter got me thinking.

The book shows how to align the big roller and the load side roller.? I was told by a man that worked for Henry on the 8k to adjust the load coil for max output.??

To do this you tune the amp on 20 meters,? Derail the chain and manually adjust the Load inductor for max output.? I did this with a tuning pulser and found 1000w!!! more output.? ?

I am now thinking of resetting it and testing the harmonics again to see if this throws off the network.??

Unfortunately, I was in the hospital over new year's and they found a herniated disk in my back, A growth on one disk and a problem in with my SI on left side.? I have been in massive pain and started physical therapy.? I don't think it's a good idea that I pull that RF deck right now. I am going to have to wait a bit and get a friend over here to help me yank it!?

C

---

From: [email protected] <[email protected]> on behalf of Jim VE7RF via groups.io <jim.thom@...>
Sent: Tuesday, January 23, 2024 7:25 AM
To: [email protected] <[email protected]>
Subject: Re: [ham-amplifiers] Tuned input

?

Clark, does the tuned input board have some sort of bypass mode ??? ? It would require one extra relay to pull that off.?
With relays wired correctly, only one relay is ever energized....(for whatever band it's on).? ?With no relays energized, the xcvr should see a wide open.? ?

?

If the output of the tuned input board is feeding that back to back un-un mess, that could easily screw things up.? You might want to at least temp bypass the 3 x un-uns and the relay that switches the back to back un-uns to the single un-un. Then retweak the Arco's.? If all is well, then remove the mess of un-uns + their relay.? Then feed the output of the tuned inputs....to the cathode..via the oem henry 4 x paralleled? .01uf coupling caps.?
A .01 uf coupling cap should not affect the tuning.? .01uf = 10,000 pf? =? 8.84 ohms of XL @ 1.8 mhz? = dick, non issue.? ?4 x .01uf caps in parallel = 40,000 pf =? 2.21 ohms of XC @ 1.8 mhz? = less than dick.?

Typ kw PI network on the output side is down 50 db for 2nd harmonic suppression.....and even more with a PI-L.? With the un-un mess bypassed / removed, you will probably see a big improvement.?

In the high gloss? Eimac catalog, they state IMD3 for the 3CX-3000A7? is -53dbc (-59db pep)...and that's at 5 kw pep out, using their 2 tone test.? ? It's one of the cleanest tubes in the entire catalog.?

Jim? ?VE7RF

On Jan 23, 2024, at 12:21 PM, W7WRX <clark@...> wrote:

?

The board has a pass-through trace if no relays are selected.? RF in and OUT.? As you select a single relay, it pulls the contacts off the jump trace and places the inductor in series.? The caps go to ground. Simple.

I was just testing the board into the amp. I understand that it will be different once installed and that Unun mess is removed.

I read online that you should use the .01 coupling cap when making your bench settings.?

I tried this and found no difference on any band.? ?There is a page online where a man shows how the coupling cap effects it with graphs. I think he had something else going on.?

Its very hard to believe the -50 figure.? That seems out of the range of reality.? ?I have measured dozens and dozens of amps here and most are -29 to -32 DB range using a radio that is -45? The only two amps that are better are my 4cx10000D, which is showing -60DB down as good as the rig and my Collins 30S1 which shows in the -45 range.?

Remember, I was NOT using a Two-tone generator for my tests that I posted for the 8K. I was simply using a RTTY carrier with the Spec An loosely coupled.? ?

I was just trying to see if the board was in fact working on all bands and trying to see how much its going to lower harmonics as I tuned each band.

I also wanted to see if the inductors would heat with a 100W RTTY carrier through them. They dont.? They run cool and imagine how much air will be on the board near the tube socket.

Once I install the board, I can run a two-tone proper test and see how the overall amp performs.? It's dirty now. Real dirty.??

One thing I will circle back on is the adjustment of the LOAD side inductor in the 8k ultra.? ?Peter got me thinking.

The book shows how to align the big roller and the load side roller.? I was told by a man that worked for Henry on the 8k to adjust the load coil for max output.??

To do this you tune the amp on 20 meters,? Derail the chain and manually adjust the Load inductor for max output.? I did this with a tuning pulser and found 1000w!!! more output.? ?

I am now thinking of resetting it and testing the harmonics again to see if this throws off the network.??

Unfortunately, I was in the hospital over new year's and they found a herniated disk in my back, A growth on one disk and a problem in with my SI on left side.? I have been in massive pain and started physical therapy.? I don't think it's a good idea that I pull that RF deck right now. I am going to have to wait a bit and get a friend over here to help me yank it!?

C

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From: [email protected] <[email protected]> on behalf of Jim VE7RF via groups.io <jim.thom@...>
Sent: Tuesday, January 23, 2024 7:25 AM
To: [email protected] <[email protected]>
Subject: Re: [ham-amplifiers] Tuned input

?

Clark, does the tuned input board have some sort of bypass mode ??? ? It would require one extra relay to pull that off.?
With relays wired correctly, only one relay is ever energized....(for whatever band it's on).? ?With no relays energized, the xcvr should see a wide open.? ?

?

If the output of the tuned input board is feeding that back to back un-un mess, that could easily screw things up.? You might want to at least temp bypass the 3 x un-uns and the relay that switches the back to back un-uns to the single un-un. Then retweak the Arco's.? If all is well, then remove the mess of un-uns + their relay.? Then feed the output of the tuned inputs....to the cathode..via the oem henry 4 x paralleled? .01uf coupling caps.?
A .01 uf coupling cap should not affect the tuning.? .01uf = 10,000 pf? =? 8.84 ohms of XL @ 1.8 mhz? = dick, non issue.? ?4 x .01uf caps in parallel = 40,000 pf =? 2.21 ohms of XC @ 1.8 mhz? = less than dick.?

Typ kw PI network on the output side is down 50 db for 2nd harmonic suppression.....and even more with a PI-L.? With the un-un mess bypassed / removed, you will probably see a big improvement.?

In the high gloss? Eimac catalog, they state IMD3 for the 3CX-3000A7? is -53dbc (-59db pep)...and that's at 5 kw pep out, using their 2 tone test.? ? It's one of the cleanest tubes in the entire catalog.?

Jim? ?VE7RF

On Jan 22, 2024, at 1:58 PM, Amp Guy Llc <kb1sel@...> wrote:

?Too long?

Amp guy llc

Amprepairguy.com

YouTube Amp repair guy

203-892-4119

On Jan 22, 2024, at 1:53 PM, Rich k0zx <k0zx.co@...> wrote:

?

[Edited Message Follows]

could you pass me a link to that page, mike... i'm on??with no results. Also tried there 2023 catalog and 204-2112

On Jan 22, 2024, at 1:53 PM, Rich k0zx <k0zx.co@...> wrote:

?

[Edited Message Follows]

could you pass me a link to that page, mike... i'm on??with no results. Also tried there 2023 catalog and 204-2112