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Re: Tuned input

 

开云体育

W7RY?? Dunno whether he made such animals, but he did provide other animals for our zoos? 8-D

Steve, K0XP


On 12/29/2023 4:50 PM, mike repinski via groups.io wrote:
That call does not seem like the one I was thinking about. Seems it was W7__? __? ? I could be wrong.

On Friday, December 29, 2023 at 07:29:58 PM EST, Alek Petkovic via groups.io <vk6apk@...> wrote:


W7IUV. Discontinued long ago.

Alek VK6APK

On 30/12/2023 8:13 am, mike repinski via groups.io wrote:
Wasn't there a 7 call ham that made such a board? Think he also made high voltage boards.

On Friday, December 29, 2023 at 06:52:48 PM EST, Steve <k0xp@...> wrote:


On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP


--
See my QRZ.com page at

AL80-B tuned input

NI5L
 

The 2 prior posts are a perfect segue into my question. My input SWR on 30 is over 3 to 1 and 12 meters is about 2 to 1. The rest seem ok.?

I have searched high and low for instructions on the proper method to tune the input slugs. I know there will be compromises between 20/30, 15/17 and AUX output per band.?

Do any of you guys have a simple way to adjust the slugs to get the input SWR down to a better place? I'm lost here.

Thanks and 73

Warren / NI5L
Re: AL-80B fan

 

LOL! I'm gonna go there mid afternoon after work and was curious how long this will take. An hour, 2 hours, 4 hours???
Bob W4JFA

On Fri, Dec 29, 2023, 8:15 PM Alek Petkovic via <vk6apk=[email protected]> wrote:

Depends on how much beer you are gonna drink.

It's actually pretty simple from memory.

73, Alek.

On 30/12/2023 9:13 am, Bob wrote:
Hi all, I'm going to help a friend replace the fan in his AL-80B amp. Is this an hour job or do I need to count on a half day or so?

Thanks, Bob W4JFA?
Re: AL-80B fan

 

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Depends on how much beer you are gonna drink.

It's actually pretty simple from memory.

73, Alek.

On 30/12/2023 9:13 am, Bob wrote:

Hi all, I'm going to help a friend replace the fan in his AL-80B amp. Is this an hour job or do I need to count on a half day or so?

Thanks, Bob W4JFA?
AL-80B fan

 

Hi all, I'm going to help a friend replace the fan in his AL-80B amp. Is this an hour job or do I need to count on a half day or so?

Thanks, Bob W4JFA?
Re: Tuned input

 

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Sorry. I forgot the link.


On 30/12/2023 8:57 am, Alek Petkovic via groups.io wrote:

No, you are right Mike. It was WD7S.

Alek.

On 30/12/2023 8:50 am, mike repinski via groups.io wrote:
That call does not seem like the one I was thinking about. Seems it was W7__? __? ? I could be wrong.

On Friday, December 29, 2023 at 07:29:58 PM EST, Alek Petkovic via groups.io <vk6apk@...> wrote:


W7IUV. Discontinued long ago.

Alek VK6APK

On 30/12/2023 8:13 am, mike repinski via groups.io wrote:
Wasn't there a 7 call ham that made such a board? Think he also made high voltage boards.

On Friday, December 29, 2023 at 06:52:48 PM EST, Steve <k0xp@...> wrote:


On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP
Re: Tuned input

 

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No, you are right Mike. It was WD7S.

Alek.

On 30/12/2023 8:50 am, mike repinski via groups.io wrote:

That call does not seem like the one I was thinking about. Seems it was W7__? __? ? I could be wrong.

On Friday, December 29, 2023 at 07:29:58 PM EST, Alek Petkovic via groups.io <vk6apk@...> wrote:


W7IUV. Discontinued long ago.

Alek VK6APK

On 30/12/2023 8:13 am, mike repinski via groups.io wrote:
Wasn't there a 7 call ham that made such a board? Think he also made high voltage boards.

On Friday, December 29, 2023 at 06:52:48 PM EST, Steve <k0xp@...> wrote:


On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP
Re: Tuned input

 

That call does not seem like the one I was thinking about. Seems it was W7__? __? ? I could be wrong.

On Friday, December 29, 2023 at 07:29:58 PM EST, Alek Petkovic via groups.io <vk6apk@...> wrote:


W7IUV. Discontinued long ago.

Alek VK6APK

On 30/12/2023 8:13 am, mike repinski via groups.io wrote:
Wasn't there a 7 call ham that made such a board? Think he also made high voltage boards.

On Friday, December 29, 2023 at 06:52:48 PM EST, Steve <k0xp@...> wrote:


On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP
Re: Tuned input

 

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I have the AT100 AMP board with the special PIC. I believe the chip is common but I don't think I know anyone that can copy them.

73, Alek VK6APK

On 30/12/2023 7:49 am, Alek Petkovic via groups.io wrote:

The amplifier version of the AT100 tuner has different stuff programmed into the PIC chip.

73, Alek VK6APK

On 30/12/2023 7:46 am, Steve wrote:
On 12/29/2023 3:38 PM, HaL Mandel wrote:

Hi Tuner-Seeker W7WRX!

?

I believe that LDG makes a board-size

tuner just for amp builders.

?

7 Band, 9 Band, I’m not sure.

?

But they advertise in QST.

?

They’ve been doing that for years.

I just bought two of them for $5 each at a local radio club auction, configured as coax-fed remote antenna tuners (RT-100 and RC-100, no longer sold) intended to be mounted at the antenna, complete with remote which also contains the bias tee (power is supplied through the coax from the remote). W4ZT (and perhaps K4POZ, too) used these for tuned input circuits on some of his amplifiers. Back when they were sold, IIRC, they were around $139 each.

73,

Steve K0XP
Re: Tuned input

 

开云体育

W7IUV. Discontinued long ago.

Alek VK6APK

On 30/12/2023 8:13 am, mike repinski via groups.io wrote:

Wasn't there a 7 call ham that made such a board? Think he also made high voltage boards.

On Friday, December 29, 2023 at 06:52:48 PM EST, Steve <k0xp@...> wrote:


On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP
Re: Tuned input

 

Wasn't there a 7 call ham that made such a board? Think he also made high voltage boards.

On Friday, December 29, 2023 at 06:52:48 PM EST, Steve <k0xp@...> wrote:


On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP
Re: Tuned input

 

开云体育

On 12/29/2023 3:45 PM, W7WRX wrote:
They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

I suppose the answer to that would be to disconnect power to the tuner after it's done its job....

Or rewire it so it only tunes when power is applied, then you remove power to keep it from self-destructing-under-drive.

Yeah, I know: VERY inconvenient! Perhaps that's why they quit making such units.

Steve, K0XP
Re: Tuned input

 

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The amplifier version of the AT100 tuner has different stuff programmed into the PIC chip.

73, Alek VK6APK

On 30/12/2023 7:46 am, Steve wrote:

On 12/29/2023 3:38 PM, HaL Mandel wrote:

Hi Tuner-Seeker W7WRX!

?

I believe that LDG makes a board-size

tuner just for amp builders.

?

7 Band, 9 Band, I’m not sure.

?

But they advertise in QST.

?

They’ve been doing that for years.

I just bought two of them for $5 each at a local radio club auction, configured as coax-fed remote antenna tuners (RT-100 and RC-100, no longer sold) intended to be mounted at the antenna, complete with remote which also contains the bias tee (power is supplied through the coax from the remote). W4ZT (and perhaps K4POZ, too) used these for tuned input circuits on some of his amplifiers. Back when they were sold, IIRC, they were around $139 each.

73,

Steve K0XP
Re: Tuned input

 

开云体育

On 12/29/2023 3:38 PM, HaL Mandel wrote:

Hi Tuner-Seeker W7WRX!

?

I believe that LDG makes a board-size

tuner just for amp builders.

?

7 Band, 9 Band, I’m not sure.

?

But they advertise in QST.

?

They’ve been doing that for years.

I just bought two of them for $5 each at a local radio club auction, configured as coax-fed remote antenna tuners (RT-100 and RC-100, no longer sold) intended to be mounted at the antenna, complete with remote which also contains the bias tee (power is supplied through the coax from the remote). W4ZT (and perhaps K4POZ, too) used these for tuned input circuits on some of his amplifiers. Back when they were sold, IIRC, they were around $139 each.

73,

Steve K0XP
Re: Tuned input

 

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They stopped making that unit years ago.? I tried using the at100 remote ldg.? It decided to tune while I was transmitting. That was it. Smoked.

C

On Dec 29, 2023 4:38 PM, "HaL Mandel via groups.io" <hmandel@...> wrote:

Hi Tuner-Seeker W7WRX!

?

I believe that LDG makes a board-size

tuner just for amp builders.

?

7 Band, 9 Band, I’m not sure.

?

But they advertise in QST.

?

They’ve been doing that for years.

?

Happy New Year weekend.

?

Hal Mandel

W4HBM
Re: Tuned input

 

开云体育

Hi Tuner-Seeker W7WRX!

?

I believe that LDG makes a board-size

tuner just for amp builders.

?

7 Band, 9 Band, I’m not sure.

?

But they advertise in QST.

?

They’ve been doing that for years.

?

Happy New Year weekend.

?

Hal Mandel

W4HBM
Tuned input

 

I am thinking of adding a tuned input to one of my amps.? Does anyone make a board?? I searched around and there seems to be nothing available.??

Does anyone have a board laying around?? Maybe from an amp supply or ameritron?

I saw there is a nice 200w low pass filter board with relays.? I guess I could repurpose it and make it a tuned input.

It needs to be relay switched.? I have control voltages for 5 bands.?
30L-1 ALC

 

What negative voltage ranges should a find in this amplifier’s ALC circuitry? I know it depends on the setting of the pot. Just curious about what variation I should see.?


Richard
WB5NEN
Re: Building my first amplifier. Where to start?

 

Just check the FU-81(GU-81M)?amplifier,?the screen grid current is 260mA for two tubes.so I guess 130mA per tube.Don't believe the rumors that the GU-81M won't work at? 21MHz and above. This is nonsense.
? .? ? ? Hsu

Steve <k0xp@...> 于2023年12月28日周四 04:08写道：

Hsu, what g2 did you use? It seems as though the GU-81M consumes a LOT of g2 current, too...

73 & HNY,

Steve K0XP


On 12/27/2023 11:54 AM, Hsu wrote:
It seems that the GU-81M is what you want. I just built an amplifier using a pair of FU-81/FM-8 (GU-81M/GI-8) with output power: 1.8-14MHz, 2900W, 21-28Mhz, 2500W.grid driven, if you only want 1KW, you can use one GU-81M on grunded-grid with a power gain of about The GU-81M has a large output capacitance, the plate capacitor must be replaced with a fixed capacitor and requires a roller inductor to tune, and at 21MHz and higher, the plate capacitor C1 is replaced by the output capacitor, as the EX8A does.?The amplifier is very quiet and requires little to no heating time, and the tubes are very inexpensive
? ? ? ?Hsu

desmond auld GI0UTE <desauld@...> 于2023年12月27日周三 16:32写道：
Peter,

You are of course correct. But due to the tappings I have options to get the voltage to where I want. The rectifier and the DC produced would be better if I settled on 3 phase, but I prefer this to be a plan b at this stage.

Thanks des?
--
See my QRZ.com page at

Re: Building my first amplifier. Where to start?

 

Hsu,

Thanks for the details on the gu81m tubes. They look great too. Too pretty to be hidden. I have settled now on two gu43b tubes. Should be happy at 2kw and push to 3kw if needed.?
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