Re: Off topic - AL80A transformer
You could try asking or searching on the amps reflector at contesting.com - I'm sure I've seen discussions about ways to re-centre the anode. Posting pictures is not permitted.
?
Steve G8GSQ
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Re: TR-4CW S meter stays to the right
Yep! All 3 finals were BAD! I threw another matched set in (Ouch!) and tomorrow I will neutralize the finals.
Mark
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Re: Off topic - AL80A transformer
Willy, I hope that the seller did not send the amp with the tube in it. That would account for that bent plate, unfortunately, and the tube is not repairable. You will need a new 3-500Z.
You can test the HV and the HV metering with the tube removed. All of your HV will be on but not connected to anything except the meter.
Any linear power supply that is designed for 60 Hz mains will run warmer on 50 Hz but in modern designs, this is not usually any problem.
I agree with Evan that the grid probably got shorted to the plate.
Good luck with fixing your amp!
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with Proton Mail secure email.
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On Tuesday, April 8th, 2025 at 4:33 PM, Willy - LU5WE via groups.io <guiye8@...> wrote: GA, and sorry for this off topic message; working in the above
mentioned amplifier, it's the USA version (no 10m, just 160 ..15), so I
think it's the US domestic version. This amplifier came to my workbench
because the owner fried the 3-500z (see plate structure tilted), fuses,
step start resistor.
Transformer wired with both winding in series (for 220V, 50 Hz in my
country, actually a little higher ... 226V), and the blower in parallel
with one winding. Blower works fine.
Turned on, and on standby I have a steady 2.2 A of mains current. I've
disconnected all secondaries.
All secondaries connected again, about 2900V somewhat flickering plate
voltage, 5.5V filament, and 13.3V (12VDC line). 2.3A mains current.
Is this high current consumption because the iron core, in this
"domestic" amp is calculated only for 60 Hz lines?.
Regards
Guillermo - LU5WE.
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Re: Off topic - AL80A transformer
I have two 3-500Zs that look like yours. ?You probably have a plate to grid short.
73,
Evan, K9SQG
??? GA, and sorry for this off topic message;? working in the above
mentioned amplifier, it's the USA version (no 10m, just 160 ..15), so I
think it's the US domestic version. This amplifier came to my workbench
because the owner fried the 3-500z (see plate structure tilted), fuses,
step start resistor.
Transformer wired with both winding in series (for 220V, 50 Hz in my
country, actually a little higher ... 226V), and the blower in parallel
with one winding. Blower works fine.
Turned on, and on standby I have a steady 2.2 A of mains current. I've
disconnected all secondaries.
All secondaries connected again, about 2900V somewhat flickering plate
voltage, 5.5V filament, and 13.3V (12VDC line). 2.3A mains current.
Is this high current consumption because the iron core, in this
"domestic" amp is calculated only for 60 Hz lines?.
Regards
Guillermo - LU5WE.
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Re: TR-4CW S meter stays to the right
Yeah I don't know what I did before to make the rig go into Xmit and blow the 5 amp power supply fuse?
I Know I tuned it up (I'm new at this on a Drake) and then I believe I was playing around with VOX and ANTI-VOX and some how it transmitted.
I also forgot to turn on the autotuner because my dipole is higher than a 2:1 by itself.
I just replaced the fuse and set the VOX fully clockwise and Anti-VOX CCW according to the manual. (I logged on here a few minutes ago
AFTER I turned my rig on) It started right up and I got stations heard. I tuned it up but SAD TO SAY I think I cooked the finals!
I'm only getting about 50 watts out on 40. I didn't try the other bands. So I guess the high VSWR cooked the tubes then blew the fuse.
I have two additional sets of finals, so when I get the chance I will throw in another set and neutralize them.
A little costly but at least she's still alive!
Mark
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Off topic - AL80A transformer
GA, and sorry for this off topic message; working in the above mentioned amplifier, it's the USA version (no 10m, just 160 ..15), so I think it's the US domestic version. This amplifier came to my workbench because the owner fried the 3-500z (see plate structure tilted), fuses, step start resistor.
Transformer wired with both winding in series (for 220V, 50 Hz in my country, actually a little higher ... 226V), and the blower in parallel with one winding. Blower works fine.
Turned on, and on standby I have a steady 2.2 A of mains current. I've disconnected all secondaries.
All secondaries connected again, about 2900V somewhat flickering plate voltage, 5.5V filament, and 13.3V (12VDC line). 2.3A mains current.
Is this high current consumption because the iron core, in this "domestic" amp is calculated only for 60 Hz lines?.
Regards
Guillermo - LU5WE.
|
Re: TR-4CW S meter stays to the right
Start with each at approximately halfway.? You should definitely not have the rig go into transmit at that setting but it is nearly impossible for it to go into transmit by itself with no mic or key connected.
Steve Wedge, W1ES
Time flies like an arrow.? Fruit flies like a banana.
Sent with secure email.
On Tuesday, April 8th, 2025 at 2:44 PM, Mark N2DMI via groups.io <markkiziuk1@...> wrote:
That¡¯s great about the cat! Does anyone know if VOX is making my rig transmit? If it could be then how do I set the VOX and anti-vox so it will NOT transmit.Thank You. Mark
On Tuesday, April 8, 2025, 2:31 PM, n4buq <n4buq@...> wrote: Ouch!? One of mine loves to "type" for me.? I still love him, though.? He's a great cat. 73, Barry - N4BUQ > I became a victim of this two months ago. My TR4CW was in cw mode. My straight > key was sitting there and while I was? outside my kitty kat laid down in front > of the rig and was up against the key. > Fried 3 precious 6JB6¡¯s > Ronnie >> On Apr 8, 2025, at 11:23?AM, n4buq < n4buq@...> wrote: >> >> ?I have a Speedex key as well.? I found that I like the blade turned over from >> ?the "normal?" way.? It allows the blade to move a bit farther away from the >> ?other half of the switch and prevents me from accidentally closing it as much. >> >> 73, >> Barry - N4BUQ >> >>> Many early rigs worked this way. I had a straight key with a built in >>> knife switch to lock key-down for transmitting in many modes. >>> >>> >>> -- >>> 73 de Mike, W1NR >>> >>> THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out... >>> programming! >>> >>> - Ruk - >>> >>> >>> >> >> >> >> >> > > > >
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Re: Another TR7 Journey begins
All 4 wafers - 2 on the LPF and 2 on the HPF?
?
73, Bill NZ0T
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Re: TR-4CW S meter stays to the right
That¡¯s great about the cat! Does anyone know if VOX is making my rig transmit? If it could be then how do I set the VOX and anti-vox so it will NOT transmit. Thank You.
On Tuesday, April 8, 2025, 2:31 PM, n4buq <n4buq@...> wrote: Ouch!? One of mine loves to "type" for me.? I still love him, though.? He's a great cat. 73, Barry - N4BUQ > I became a victim of this two months ago. My TR4CW was in cw mode. My straight > key was sitting there and while I was? outside my kitty kat laid down in front > of the rig and was up against the key. > Fried 3 precious 6JB6¡¯s > Ronnie >> On Apr 8, 2025, at 11:23?AM, n4buq < n4buq@...> wrote: >> >> ?I have a Speedex key as well.? I found that I like the blade turned over from >> ?the "normal?" way.? It allows the blade to move a bit farther away from the >> ?other half of the switch and prevents me from accidentally closing it as much. >> >> 73, >> Barry - N4BUQ >> >>> Many early rigs worked this way. I had a straight key with a built in >>> knife switch to lock key-down for transmitting in many modes. >>> >>> >>> -- >>> 73 de Mike, W1NR >>> >>> THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out... >>> programming! >>> >>> - Ruk - >>> >>> >>> >> >> >> >> >> > > > >
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Re: TR-4CW S meter stays to the right
Ouch! One of mine loves to "type" for me. I still love him, though. He's a great cat.
73,
Barry - N4BUQ
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I became a victim of this two months ago. My TR4CW was in cw mode. My straight
key was sitting there and while I was outside my kitty kat laid down in front
of the rig and was up against the key.
Fried 3 precious 6JB6¡¯s
Ronnie
On Apr 8, 2025, at 11:23?AM, n4buq <n4buq@...> wrote:
?I have a Speedex key as well. I found that I like the blade turned over from
?the "normal?" way. It allows the blade to move a bit farther away from the
?other half of the switch and prevents me from accidentally closing it as much.
73,
Barry - N4BUQ
Many early rigs worked this way. I had a straight key with a built in
knife switch to lock key-down for transmitting in many modes.
--
73 de Mike, W1NR
THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out...
programming!
- Ruk -
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Re: Another TR7 Journey begins
Bill I just happen to have my TR7 on the bench trying to get the CW working and they are both the same way up on mine depending on where the band switch is. Hope that helps.
73, Jim VE1RB
Dumb question - do the switch wafers in the LPF and HPF modules all have the notch pointing the same way?? I turned the bandswitch knob so the flat sides of the rod were on the top and bottom and marked them that way.? The notch in the wafers on the LPF module were both pointing up as are the two on the HPF.? I ask because the Heathkit HW and SB series have one switchboard that must be installed with the notch in the opposite direction from the others and I can't find anything in the TR7 service manual about orientation of the wafers.? I want to make sure I have this correct!
?
73, Bill NZ0T
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Re: TR-4CW S meter stays to the right
I became a victim of this two months ago. My TR4CW was in cw mode. My straight key was sitting there and while I was outside my kitty kat laid down in front of the rig and was up against the key.
Fried 3 precious 6JB6¡¯s
Ronnie
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Show quoted text
On Apr 8, 2025, at 11:23?AM, n4buq <n4buq@...> wrote:
?I have a Speedex key as well. I found that I like the blade turned over from the "normal?" way. It allows the blade to move a bit farther away from the other half of the switch and prevents me from accidentally closing it as much.
73,
Barry - N4BUQ
Many early rigs worked this way. I had a straight key with a built in
knife switch to lock key-down for transmitting in many modes.
--
73 de Mike, W1NR
THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out...
programming!
- Ruk -
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Also:
?
http://ja1vtu.scm-net.or.jp/manuals/Drake/Manuals/Drake%20QXer%20(receiver%20accessory)%20WW.pdf
?
73
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Re: Another TR7 Journey begins
Dumb question - do the switch wafers in the LPF and HPF modules all have the notch pointing the same way?? I turned the bandswitch knob so the flat sides of the rod were on the top and bottom and marked them that way.? The notch in the wafers on the LPF module were both pointing up as are the two on the HPF.? I ask because the Heathkit HW and SB series have one switchboard that must be installed with the notch in the opposite direction from the others and I can't find anything in the TR7 service manual about orientation of the wafers.? I want to make sure I have this correct!
?
73, Bill NZ0T
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Re: TR-4CW S meter stays to the right
I have a Speedex key as well. I found that I like the blade turned over from the "normal?" way. It allows the blade to move a bit farther away from the other half of the switch and prevents me from accidentally closing it as much.
73,
Barry - N4BUQ
toggle quoted message
Show quoted text
Many early rigs worked this way. I had a straight key with a built in
knife switch to lock key-down for transmitting in many modes.
--
73 de Mike, W1NR
THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out...
programming!
- Ruk -
|
Re: TR-4CW S meter stays to the right
Many early rigs worked this way. I had a straight key with a built in knife switch to lock key-down for transmitting in many modes.
--
73 de Mike, W1NR
THAT was the equation. EXISTENCE!... SURVIVAL... must cancel out... programming!
- Ruk -
|
Re: Tuning a pi-Network Output
BTW, I bought 1kV NP0 caps.? Apparently the original is 2kV.? Does that really need to be a 2kV cap?
I see that it connects between +650V and +250V so nominally it's only seeing 400V; however, is it the case that modulation peaks would require higher than a 1kV part - at least to be on the safe[r] side?
I half-way wondered that Drake may have had these on hand for other rigs and used what they had instead of stocking multiple voltage values.
Thanks, Barry - N4BUQ
From: "Steve Wedge, W1ES/4 via groups.io" <w1es@...>
To: "DRAKE-RADIO" <[email protected]>
Sent: Tuesday, April 8, 2025 8:08:13 AM
Subject: Re: [DRAKE-RADIO] Tuning a pi-Network Output
GE tubes should work fine with the ¡°stock¡± cap setup.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Tue, Apr 8, 2025 at 08:39, n4buq <n4buq@...> wrote:
The schematic I have shows 12.5pF.? I'm not looking at it at the moment, but I think the one that was in there is (was) a 12pF so I presume a 12pF or 13pF should do fine. I'll need to get one ordered.
My tubes are GE.
Thanks,
Barry - N4BUQ
Yes, it needs to be the value shown in the schematic, in parallel with the variable. Substantially higher values are not recommended and the original values should be used if you¡¯re not using RCA tubes.?
I¡¯m just getting up and so don¡¯t have the manual in front of me and can¡¯t remember the exact values.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Mon, Apr 7, 2025 at 19:53, n4buq <
n4buq@...> wrote:
Regardless of how I go about it, with C77 in place, C76 minimizes the output at fully open and with C77 disconnected, C76 minimizes the output at fully closed.
With one leg of C77 disconnected, I started checking its value and I kept getting very weird values: either several microfarads (yes with a "micro") or somewhere around 140 picofarads.? I decided to de-solder the other end and checked it again and it went complete to "Unknown or damaged part" on my T7 component checker.? Apparently it was on the verge of completely bad and de-soldering finished it off (short lead on one end).
I don't have a proper replacement yet but I do have a 27pF 500V SM that I might throw in there just to see if changes things much the same way the original cap did.? I presume it will still be too much extra capacitance but it might be interesting to see, with it in circuit and even though it's about double the original capacitance, whether C76 gets the output closer to a full null when it's at or nearly fully open.
I presume a disk ceramic is still the appropriate cap to use for C76?
Thanks,
Barry - N4bUQ
Steve,
I'll run through it that way.? As I said, all I did was monitor the output at the antenna jack with no dummy load.? Since the controls didn't seem to affect what I was seeing on the scope.? Perhaps it was mostly due to there not being a proper load resistance.? I'll report back - hopefully tomorrow.
Thanks so much!
Barry - N4BUQ
Just to check, the transmitter should be tuned for a dip at the highest frequency or where specified by the procedure. You then leave the plate and load controls as they are, then disconnect the screen supply. Then, after disconnecting the screen supply, go into transmit with the minimum drive to see a reading on the scope. The transmitter remains connected to the dummy load. Adjust the neut cap for minimum amplitude. Reconnect the screen supply and verify that max power out coincides with plate current dip.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Sun, Apr 6, 2025 at 17:01, n4buq <
n4buq@...> wrote:
Yesterday, I disconnected the screen grid supply to the PA tubes and monitored the output at the antenna jack with my scope.? While I can see a reduction in what appears to be the spurious oscillation, that occurs at the point where C76 is fully open (which might explain why it was in that position when I saw it earlier).? I find this odd and likely a problem.? Unlike needing to change C77 just a bit for some of the tube brands, it appears there's already way too much there.
I disconnected C77 and that didn't have much, if any, affect on the value I'm seeing across C76.? That reading is somewhere around 40 nF which I think may be very much out of line as to what it should be.? Changing the band switch, varying the tune control, and varying the plate circuit caps had little, if any, affect on that capacitance value.? Disconnecting the plate connections also didn't change it much, if any.
Does that reading make any sense?? I'm thinking it doesn't and something else is very wrong but I'm at a loss to explain it.? Is what I'm seeing completely abnormal?
Thanks,
Barry - N4BUQ
Mike,
I've read where there are some circuits that can have individual circuitry for each band that allows for "tweaking" the neutralization on each of the lower bands.? Of course, the Drake circuits don't have that but I presume it is possible.
I'm currently only using the watt meter in my MN-2000 for CW as I don't have a mic wired up for the TR-4 yet.
Thanks,
Barry - N4BUQ
Barry and Steve,
?
Neutralizing an RF amplifier is occurs ONLY on the frequency
it is performed on. This typically is done on 10 meters on an amateur
radio transmitter/transceiver final amplifier.
?
Once the neutralizing adjustment is performed on 10 meters, do NOT
make any changes to the neutralizing circuit on any lower band. You
will not see the same maximum RF output at maximum PLATE current
dip on any lower band. This is NORMAL and should NOT mean you have
to make changes to the neutralizing circuit on the lower bands.
?
Follow the manufacturer's transmitter loading/tuning instructions
in the operator's manual.
?
The Drake MN-2000 watt meter is an "average watt meter". Do not
expect to see "SSB PEP" RF levels on the MN-2000 watt meter.
?
73
Mike W5RKL
?
?
?
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Re: TR-4CW S meter stays to the right
I believe I was in SSB mode and not CW/X Mode.
Almost 90 percent positive.
Mark
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Re: TR-4CW S meter stays to the right
BTW, all TR-3/4 versions are like this. Earlier T-4 and T-4X are also this way. Conversely, if you leave an open key plugged in, you won¡¯t get TUNE, SSB or AM to work. The rig will key the relay but there¡¯ll be no power out/modulation.?
Later T-4X and all subsequent separate transmitters can leave the key in the jack and still fully work in the other modes without closing the key.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Tue, Apr 8, 2025 at 09:49, n4buq < n4buq@...> wrote:
If the TR-4CW is like the TR-4 (and I believe it is), if the sideband switch is at "X", the mode switch is in "X-CW", and there is no key plugged in (or if there is a key but its contacts are closed), then the rig will be in transmit.
Barry - NB4BUQ
From: "Mark N2DMI via groups.io" <markkiziuk1@...>
To: "DRAKE-RADIO" <[email protected]>
Sent: Tuesday, April 8, 2025 8:43:53 AM
Subject: Re: [DRAKE-RADIO] TR-4CW S meter stays to the right
OK. How would it go into transmit without keying the mike?
VOX circuit?
I am not that familiar with Vox?
But I was also trying to set vox and anti-vox according to the instruction manual.
Where should my vox and anti-vox be set so that outside noise won¡¯t trip the transmit?
Mark
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Re: TR-4CW S meter stays to the right
Correct.?
Steve Wedge, W1ES
Time flies like an arrow. Fruit flies like a banana.
On Tue, Apr 8, 2025 at 09:49, n4buq < n4buq@...> wrote:
If the TR-4CW is like the TR-4 (and I believe it is), if the sideband switch is at "X", the mode switch is in "X-CW", and there is no key plugged in (or if there is a key but its contacts are closed), then the rig will be in transmit.
Barry - NB4BUQ
From: "Mark N2DMI via groups.io" <markkiziuk1@...>
To: "DRAKE-RADIO" <[email protected]>
Sent: Tuesday, April 8, 2025 8:43:53 AM
Subject: Re: [DRAKE-RADIO] TR-4CW S meter stays to the right
OK. How would it go into transmit without keying the mike?
VOX circuit?
I am not that familiar with Vox?
But I was also trying to set vox and anti-vox according to the instruction manual.
Where should my vox and anti-vox be set so that outside noise won¡¯t trip the transmit?
Mark
|
Mark N2DMI
Ronnie Hull - W5SUM
