Re: Tuning a pi-Network Output
If the original was 2KV that is the minimum that I would replace it with. On Tue, 8 Apr 2025 11:12:59 -0400 (EDT) "n4buq via groups.io" <n4buq@...> wrote: BTW, I bought 1kV NP0 caps. Apparently the original is 2kV. Does that really need to be a 2kV cap? -- 73 -Jim NU0C
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I have the code. if you want I can send it to you. On Tue, 08 Apr 2025 16:48:30 -0700 "Diego Gallo via groups.io" <lu3hdd@...> wrote: In my country, my friend is able to source the DM54S287 memory device. Our current project is to generate the binary code that will be programmed into the memory to ensure proper system operation. -- 73 -Jim NU0C
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Re: Another TR7 Journey begins
Thanks for the verification!?
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Thank you very much, Jim.
Your explanation is spot on. We¡¯ve been able to make significant progress and arrive at this diagnosis thanks to the information shared in this forum, for which we are truly grateful. Our next step will be to remove the PROM in order to verify the remaining signal bands. We will also check whether the equipment is capable of transmitting and receiving properly.
In my country, my friend is able to source the DM54S287 memory device. Our current project is to generate the binary code that will be programmed into the memory to ensure proper system operation.
We¡¯ll continue to share any developments as they arise.
73 Dx¡¯s
LU3HDD
Diego
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Re: Another TR7 Journey begins
Yes on the 4.5 to 7 band switch setting the flat is on the top as you can see it easily and the way it all wafers must be aligned the same with the flat side.
Jim VE1RB
All 4 wafers - 2 on the LPF and 2 on the HPF?
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73, Bill NZ0T
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Re: Off topic - AL80A transformer
Many thanks for the answers.
The owner is a local ham, he was using it without problem until the "boommm..". I suspect he was pushing it too hard.
There's indeed a nice short between plate and grid. A replacement tube is already at hand, but I want to clear all other things before I plug it into work.
My main concern is about the high value of primary current (in standby mode), without any major load.. and the HV flickering .. perhaps I'll try the transformer for isolation with a megger.
Regards
Guillermo - LU5WE.
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El 8/4/25 a las 17:33, Willy - LU5WE via groups.io escribi¨®: ????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
A highish SWR won't ruin the finals in and of itself (if you can dip the plate current below the recommended limit... ) but leaving it in transmit for extended periods of time? will cook the finals.
Just to scale things a bit.... I can tune a Drake rig in probably 10 to 15? seconds of total transmit time , spaced into 3-4 separate transmissions of a few seconds each. I never load the rig up to max plate current.
I keep a muffin fan pulling air out of the final cage.
I almost never have final tubes go soft
Glad the rig was ok other than tubes. The Drake tune up instructions are pretty good, but are there any locals there familiar with tuning up tube rigs you might get help from???
73 John K5MO
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: T-4XC Meter Shunt Resistor?
? ? ?Roger on the FOCMKEAS Amazon vendor below.? I have one better than that.? A while back, all of us standby passengers were staring at the priority monitor display at an Alaska Airlines gate.? The rank order of standby passengers is listed by the first three
letters of the (hopeful) passenger's last name with a space followed by the first initial of his or her first name.
? ? ?As a Japanese gentleman checked in, we all did a double take.? It turns out that his name was Ueno Fukiyama (or at least that's how it was printed out in Romaji in ALL CAPS.)? I commented to my XYL: "Well, that's a little hostile!"? It turned out that
there were enough open seats for everybody to get on board, so all's well that ended well.
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Thanks Dan & Peter!
?
R49 came in at around 1600 ohms, replacing tomorrow. Surprisingly, Amazon has them but you have to buy in bulk. I just received the unusual message after my order,?
"Your order for 10PCS 1.5K Ohm Resistor from FOCMKEAS has been confirmed"
Can't wait to read the review comments with a vendor name like that.?
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I'm replacing the 3.3 ohm with a precision 1% and I'm going to run leads from it to banana jacks that I'm installing in the extra holes next to the cinch jones connector.?
?
At 60mA bias I should read a drop of .198V across the jacks. With that funky non-zero meter in the T-4, I wonder what the actual bias is that I'm currently running.?
?
Hopefully the extra wire length won't create any parasitic hooligans.?
--
Craig/W8CS
Greenville, SC
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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.
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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.
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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?
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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!
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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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Jim Shorney
Craig KL7H
Mark N2DMI
Ronnie Hull - W5SUM