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UNDER CONSTRUCTION!!!!!!!!!

Götting HG70D 2M FM-SSB-AM transceiver repair

This 50 year old transceiver had no power output.
There were several reasons for this.
First, all foil trimmers in the PA were fried...., the needed to be replaced
It also turned out that a 10 ohm 5 Watt resistor became 8 Kohm...
It also turned out that no 24V was present on the PA so I checked the 2N3055, this is the switching transistor and voltage regulator for the PA supply voltage.
The 2N3055 turned out to be defective, the transistor that switches the 2N3055 at TX the BC140-16 was also defective.
All parts replaced and now the set works again!

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Götting HG70C 2M FM-SSB-AM transceiver

A quick look inside the Götting HG70C.
This is the C version, so with 2 tubes in the PA

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Yaesu FT736R repairs.

I've had 3 Yaesu FT736r's on the measurement table.

I adjusted all 3 according the service manual.
First repair:
Inimages/trx_bench/DSCF3639groot.jpg one I had to repair the power supply. This is a major problem with this device, the electrolytic capacitors all need to be renewed to bring them back to life.
It is also best to replace the power resistor for a larger wattage. I also renewed the S meter lighting.
Because there is no ctcss encoder as standard, I bought a kit and made it myself and placed it in the transceiver

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Second repair:
The second repair was more a modification....
I had bought a 2nd hand 736.
When it came in and unpacked it, I felt and heard that there was something loose in it.
Before I plugged it in, I thought it was wise to open it to see what was wrong.
What I saw was AMAZING! ...
I saw that the original power supply was no longer in it, and an external power supply was stuck in it instead ...
the case of that external power supply had been removed to fit the case of the 736 ....
That was loose and the noise caused was the fan that had come loose during transport ...
I had never seen this solution (HI)
I took out the entire power supply (and turned it back into an external power supply)
The 736 was brought back to its original condition without a power supply.
This eventually worked on external 13.8 volts
Of course the seller didn't know anything ... He could have bought it like that himself ... I don't want to rule that out.

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Third repair
Unfortunately, the processor board of this transceiver was defective and unfortunately there is no new processor available, not even 2nd hand.
The transceiver stopped transmitting and there was no way around this.
something must have gone wrong connecting an external power amplifier.
Via the PTT there must have been voltage on the processor ... unfortunately this is not secured and therefore the processor has probably become defective
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The FT736 in action