Re: Only showing 9MHZ on DD-103
Hey Gary and everyone, when I come home from work this afternoon I will try to set up the Drake and take those measurements. It would be nice to get it working.
Mark
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Re: Only showing 9MHZ on DD-103
First check to see that you have the 10 volts DC to the PTO. Then measure the resistance from the PTO Output to ground. It should be above 270 ohms.
Then use your scope or spectrum analyzer to observe the PTO Output at the PTO and then at ?V1 pin 2. You should clearly see the PTO signal there.
Report back.
Gary
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On Apr 18, 2025, at 8:18?AM, Mark N2DMI via groups.io <markkiziuk1@...> wrote:
? Hi Ken, when I come home from work I can look more at the rig and hopefully answer those questions. And yes I have the manual, procedure and service manual.
Mark
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Re: Only showing 9MHZ on DD-103
The IF frequency is 9 MHz but you should not be seeing it at R48. It seams to me that any 9 Mhz leakage should not be strong enough to be picked up by the counter over the PTO signal. On Fri, 18 Apr 2025 18:23:22 -0700 "Mark N2DMI via groups.io" <markkiziuk1@...> wrote: The 9Mhz showing up on my DD-103 must mean something??
9Mhz is in the rig somewhere, right?
Mark -- 73 -Jim NU0C
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Re: Only showing 9MHZ on DD-103
It's a high impedance circuit so drop across 100 Ohms would be minimal. What I would suggest is that you check R48 for visible damage, bad solder connections, and measure it for value with your Ohmmeter. On Fri, 18 Apr 2025 18:19:18 -0700 "Mark N2DMI via groups.io" <markkiziuk1@...> wrote: Then re-connect the PTO signal wire back to R48 and use the O-scope to measure the voltage to where the PTO signal wire gets connected to R48 and check to see how
much of a voltage drop I get?
Well I believe I would get some kind of a voltage drop.
I think since I have also a TR-4CW is to do the same two measurements to my other rig so that I know what the voltage measurements on an O-scope should be otherwise I would not know if the 2 measurements on my TR-4CW/RIT are correct. -- 73 -Jim NU0C
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Re: Only showing 9MHZ on DD-103
The 9Mhz showing up on my DD-103 must mean something??
9Mhz is in the rig somewhere, right?
Mark
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Re: Only showing 9MHZ on DD-103
I think its R148 and not R48 Ken.
Mark
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Re: Only showing 9MHZ on DD-103
Ken, I do have an O-scope. So your saying to remove the PTO signal wire from R48 and then measure the PTO output signal voltage.
Then re-connect the PTO signal wire back to R48 and use the O-scope to measure the voltage to where the PTO signal wire gets connected to R48 and check to see how
much of a voltage drop I get?
Well I believe I would get some kind of a voltage drop.
I think since I have also a TR-4CW is to do the same two measurements to my other rig so that I know what the voltage measurements on an O-scope should be otherwise I would not know if the 2 measurements on my TR-4CW/RIT are correct.
Mark
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Re: Only showing 9MHZ on DD-103
Looks like R48 on the marginal scans of schematics that I have. 100 Ohms feeding the grid. C12 would be included in "checks around V1". On Fri, 18 Apr 2025 21:06:38 -0400 (EDT) "n4buq via groups.io" <n4buq@...> wrote: Did you possibly mean R148?
Also, the signal would go from that resistor through C12 to the grid.
73,
Barry - N4BUQ
Here is your circuit. The PTO feeds the grid of V1B via R48. I think I would
look at R48 first, then make some checks around V1.
Disclaimer: I have not been inside any TR4 in decades.
On Fri, 18 Apr 2025 16:25:17 -0700
"Mark N2DMI via groups.io" <markkiziuk1@...> wrote:
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the
signal was being loaded down and I still have signal output that tracks the
PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it
reads 9Mhz.
--
73
-Jim
NU0C
-- 73 -Jim NU0C
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Re: Only showing 9MHZ on DD-103
I meant "fact", not "face". Ugh. Friday night fingers at work.
Barry - N4BUQ
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Apologies. I wasn't thinking of the face that Mark has a TR-4C, not a plain
TR-4. R48 is indeed the correct resistor in the C model.
73,
Barry - N4BUQ
Did you possibly mean R148?
Also, the signal would go from that resistor through C12 to the grid.
73,
Barry - N4BUQ
Here is your circuit. The PTO feeds the grid of V1B via R48. I think I would
look at R48 first, then make some checks around V1.
Disclaimer: I have not been inside any TR4 in decades.
On Fri, 18 Apr 2025 16:25:17 -0700
"Mark N2DMI via groups.io" <markkiziuk1@...> wrote:
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the
signal was being loaded down and I still have signal output that tracks the
PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it
reads 9Mhz.
--
73
-Jim
NU0C
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Re: Only showing 9MHZ on DD-103
Apologies. I wasn't thinking of the face that Mark has a TR-4C, not a plain TR-4. R48 is indeed the correct resistor in the C model.
73,
Barry - N4BUQ
toggle quoted message
Show quoted text
Did you possibly mean R148?
Also, the signal would go from that resistor through C12 to the grid.
73,
Barry - N4BUQ
Here is your circuit. The PTO feeds the grid of V1B via R48. I think I would
look at R48 first, then make some checks around V1.
Disclaimer: I have not been inside any TR4 in decades.
On Fri, 18 Apr 2025 16:25:17 -0700
"Mark N2DMI via groups.io" <markkiziuk1@...> wrote:
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the
signal was being loaded down and I still have signal output that tracks the
PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it
reads 9Mhz.
--
73
-Jim
NU0C
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Re: Only showing 9MHZ on DD-103
Forgot the attachment. On Fri, 18 Apr 2025 19:43:58 -0500 "Jim Shorney via groups.io" <jimNU0C@...> wrote: Here is your circuit. The PTO feeds the grid of V1B via R48. I think I would look at R48 first, then make some checks around V1.
Disclaimer: I have not been inside any TR4 in decades.
On Fri, 18 Apr 2025 16:25:17 -0700
"Mark N2DMI via groups.io" <markkiziuk1@...> wrote:
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the signal was being loaded down and I still have signal output that tracks the PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it reads 9Mhz. -- 73 -Jim NU0C
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Re: Only showing 9MHZ on DD-103
Did you possibly mean R148?
Also, the signal would go from that resistor through C12 to the grid.
73,
Barry - N4BUQ
toggle quoted message
Show quoted text
Here is your circuit. The PTO feeds the grid of V1B via R48. I think I would
look at R48 first, then make some checks around V1.
Disclaimer: I have not been inside any TR4 in decades.
On Fri, 18 Apr 2025 16:25:17 -0700
"Mark N2DMI via groups.io" <markkiziuk1@...> wrote:
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the
signal was being loaded down and I still have signal output that tracks the
PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it
reads 9Mhz.
--
73
-Jim
NU0C
|
Re: Only showing 9MHZ on DD-103
Here is your circuit. The PTO feeds the grid of V1B via R48. I think I would look at R48 first, then make some checks around V1. Disclaimer: I have not been inside any TR4 in decades. On Fri, 18 Apr 2025 16:25:17 -0700 "Mark N2DMI via groups.io" <markkiziuk1@...> wrote: I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the signal was being loaded down and I still have signal output that tracks the PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it reads 9Mhz. -- 73 -Jim NU0C
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Re: Only showing 9MHZ on DD-103
Sorry, Mark, I called it a VFO but I meant PTO.?
Do you have an oscilloscope? You could verify that the PTO signal is not being?attenuated or determining where it is being lost.?
On Fri, Apr 18, 2025 at 7:25?PM Mark N2DMI via <markkiziuk1= [email protected]> wrote: I have a TR4-CW and I have a TR4-CW/RIT.
I purchased both rigs less than 2 months ago.
I also purchased a DD-103 which was wired for TR4.
The DD-103 to the best of my knowledge is wired correctly.
The DD-103 worked on both the TR4-CW and on the TR4-CW/RIT.
I noticed that when I turned the main tuning knob on the newly acquired TR4_CW/RIT that with every revolution it would make some kind of a scraping sound.
I posted on this group of what it could be?
I took alot of photos of the 4 wires and the disassembly of the PTO. It was pretty much straight forward removing 4 wires and removing the screws and such for the PTO.
After removal of the PTO I discovered that gears did not line up correctly. By lightly bending a piece of metal that one of the gears was attached to quickly fixed the mis-alignment.
I then simply re-installed the PTO and connected the 4 wires correctly!
I then connected my rig to my antenna but heard no stations.
I then removed the PTO, connected an external 9 Volt (I believe it was 9V?) and used my signal generator to pick up the PTO signal from its wire.
Perfect signal, perfect strength and tracked up and down entirely across the band. I think it outputted 4.8-5.6 Mhz. Nothing wrong with the PTO!
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the signal was being loaded down and I still have signal output that tracks the PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it reads 9Mhz.
And no I have not monitored the internal TR-4 VFO. I don't know where that is?
Mark
?
?
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Re: Only showing 9MHZ on DD-103
I have a TR4-CW and I have a TR4-CW/RIT.
I purchased both rigs less than 2 months ago.
I also purchased a DD-103 which was wired for TR4.
The DD-103 to the best of my knowledge is wired correctly.
The DD-103 worked on both the TR4-CW and on the TR4-CW/RIT.
I noticed that when I turned the main tuning knob on the newly acquired TR4_CW/RIT that with every revolution it would make some kind of a scraping sound.
I posted on this group of what it could be?
I took alot of photos of the 4 wires and the disassembly of the PTO. It was pretty much straight forward removing 4 wires and removing the screws and such for the PTO.
After removal of the PTO I discovered that gears did not line up correctly. By lightly bending a piece of metal that one of the gears was attached to quickly fixed the mis-alignment.
I then simply re-installed the PTO and connected the 4 wires correctly!
I then connected my rig to my antenna but heard no stations.
I then removed the PTO, connected an external 9 Volt (I believe it was 9V?) and used my signal generator to pick up the PTO signal from its wire.
Perfect signal, perfect strength and tracked up and down entirely across the band. I think it outputted 4.8-5.6 Mhz. Nothing wrong with the PTO!
I connected the wires back up to the PTO and again no signals!
I then put the spectrum analyzer close to the PTO signal output to see if the signal was being loaded down and I still have signal output that tracks the PTO.
Out of curiosity I connected my working DD-103 to the jones connector and it reads 9Mhz.
And no I have not monitored the internal TR-4 VFO. I don't know where that is?
Mark
?
?
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Re: Only showing 9MHZ on DD-103
Hi Mark-
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I think we've all been in your shoes before. You disassemble something that works, and when you put it back together it no longer works.?
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The only thing that has saved my bacon over the years when I work on this gear is to SLOW DOWN and do the following:?
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- take notes on everything that you do. Describe what is is that are doing as if someone else was going to pick up the job. I have notes on my rigs from 1997.?
- take pictures and sketch things out
If you follow a very structured pattern, you're much more likely to have a working radio after mods and the initial smoke test. This is what HeathKit did so well years ago.?
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If something doesn't work after I've messed with it, I 100% know that it's something that I have done...now I just need to follow my own breadcrumb trail to figure out what I did wrong.?
--
Craig/W8CS
Greenville, SC
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Hi Mark, the IC was fine, it was ME that plugged in the small PS board one pin off...and roasted the IC that way. I would never have guessed/found that issue had Dieter not owned up to doing the same before me. I used the IC socket as well, as the board traces would probably not survive another unsoldering/replacement cycle.?
--
Craig/W8CS
Greenville, SC
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Craig,
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Interesting that you had trouble with that particular IC. So did I, on my low-SN TR-7.
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I replaced with a CD4066, as that's what I had to hand. The 4066 is a somewhat improved version of the 4016, as I recall. I put the replacement on a socket, just in case I ever have to go there again;-)
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Regards,
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Mark, G4FPH.
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Re: TR4310 HF Transceiver
Tilman,
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The issue you have could be caused by the 8-bit range data words being sent to the Translator Board being corrupt for all of the ranges in 10 - 15 MHz, sending the VCO into a spin. It could also be some issue with the major loop VCO Board itself, where the VCO was failing to behave properly in just part of it's range.
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Jim has reminded us of the importance of a good quality +24 Volt from the Power Supply to the correct functioning of both the low- and high-bands VCO in the major loop synthesiser. Certainly one to check, but I would expect trouble with lock on the bands above 15 MHz were there an issue there. Could be some other failing component in the low-bands VCO. A straight swap of the VCO Board would tell us a lot!
?
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If you have access to a Jumper Board, part of the Service Kit for a Drake TR-7, you could try removing the VRTO Digital Board and install the Jumper Board between the Digital Control and Translator Boards. You wrote previously that the VCO was glitching on the 'hands-off' startup frequency for the 10 - 15 MHz range of 12.250 MHz. If it continued to glitch with the Jumper Board in place of the VRTO Digital Board, that would suggest a VCO issue. If the glitching stopped when using the Jumper Board, that would suggest an issue on the VRTO Digital Board.
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I had a similar issue when I was repairing my TR4310. In fact, I had two issues in this area: (1) Corrupted data in the U201 PROM on the Digital Control Board for certain ranges. Plus, (2) The up/down counters on the VRTO Digital Board were further corrupting the data for nearly all ranges.
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I have uploaded an Excel spreadsheet to the files area of the group (TR4310 folder) that I made to help me understand what was happening. The information in this should help you to verify the correctness of the data (incoming and outgoing) on the VRTO Digital Board.
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Regards,
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Mark.
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File /TR4310/Drake TR4310 Band Codes And AUX-7 G4FPH Group.xlsx uploaded
#file-notice
The following items have been added to the Files area of the [email protected] group.
By: atlasstuff <g4fph@...>
Description:
Excel sheet containing information for debugging band / range code issues.
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Mark N2DMI
Jim Shorney
Craig W8CS