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Thank's for the get back brandon.
I pulled D53, it checked ok on my transistor tester.
No info on 1S2473 in Mouser or NTE.
Did a interchange on it and found a 1N4148 is the interchange.
Installed a new 1N4248 (Easy'r to put new in with long lead's) and still nothing.
The Tram is done and back on the 458.
Swapped L37, L38 and FET7 from the working 458 to the inop 458 and no change, The working 458 is working with part's from the inop 458.
I've compared all voltages into L37 at point's 17, 144,143 and compared between the two radio's and every thing and both...
That procedure in the manual to neutralize is a joke, Nomad's method is the best,
BTW Mr, Nomad, In our talk on the phone on 3/26/24, I told ya about my D-201 putting out a carrier on SSB, I ran through the by-gum-and-by-gosh method and i got USB to stop throwing a carrier, But no luck on LSB...
Well it was a good idea to try the L39, But the working 458 still work's and the inop one is still inop.
One thing i did was make sure the ferrite core will turn in the working one before the swap and i know the one removed from the inop one turn's.
Once i swapped them both over, and keyed the...
Thank's TM86.
I saw your comment in this thread...
https://www.worldwidedx.com/threads/realistic-trc-457-stock-freq-issue.267985/
I'll trade the L39 from the working one to the inop 458
It all started when a friend told me about his cherry TRC-458, He'd has several tech's work on it and he wanted me to swap out all the electrolytic cap's.
He said it just DIDN'T seam rite, He though the audio CLIPPED out but it was his call to change the cap's. So i volunteered my services...
As far as i can tell, With a S9 signal into it, the squelch kill's the sound around 2 O'clock, But I've only got the Synthesizer alignment done so far,
What's everyone think of to use this as a replacement for VR12?
This one?????
https://www.mouser.com/ProductDetail/Amphenol-Piher/PT10LV10-501A2020-S?qs=pCZPOPZMYPh0kKMSfZYsdg%3D%3D
Or this one...
SO Just to report (As many times it doesn't) I found TR12 to be at fault, I will now perform the alignment and do further over the air testing before returning the radio to the customer.
Thank's everyone for your help and i hope if someone else has this problem, going through these 5 pages, it...
Hey Brandon,
You are DA MAN. I pulled out VR12 and ohm check it and it's fubar,
I don't see that part number anywhere on the WWW, I have a donar part's cobra 138XLR and stole all the VR style semi fixed resistor's out and found one marked around 500, Installed it and BAM I have transmit audio...
Hey Brandon,
Look's like it's time to get on the hunt for a replacement VR12.
It still has me wondering. If VR12 is fubar (and it appears it is) Will this also affect SSB?
Mabey i need to check everything around TR34 as well and VR11.
Hey Bob.
I put a 1N4148 in the D64 spot and at C of TR26 i have,,,
4.362 VDC AM RX.
4.535 VDC SSB RX
1.825 VDC AM TX
4.535 VDC SSB TX
That is when the mic audio is not working and Failing.
You didn't say what mode to check C of TR26, so i did them all.
Hey Bob.
I need to put a diode in D64 location before i can test this.
I don't have the 1S1588 Diode and it's questionable if the D64 diode was correct and i can't read it.
NTE say's the 1S1588 interchanges to the NTE519, as well 1N914 and 1N4148 interchange to NTE 519 and i stock the 1N914 and...
I pulled D64, Unable to read what it say's on it,
Tested as a diode.
uf - 701MV
C 4pf
Multimeter set in Diode mode and with the + lead on anode side and - on cathode side it read's .586. Reverse lead's and it say's .of
Tested the radio with D64 removed No Transmit Modulation anywhere,
I did...
Hey Bob.
With eather TR24 or TR25 removed i DO have transmit modulation in AM, SSB and PA.
With TR26 Removed i only have transmit modulation in SSB, No Transmit modulation in AM and PA is choppy out the speaker and no voice out the speaker.
Hey Brandon.
I installed a new 1.5K resistor in R165,
Checked voltages across D64.
In SSB the Anode side has 5.156 VDC and Cathode side has 4.884 VDC
At the Cathode of D64 with VR12 Full CW the voltage is 4..888 VDC and with VR12 Full CCW the voltage is 4.743 VDC.
The Voltages at the Base of...
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