I have learned a lot in the last while about radio repair
and the like. The Yaesu FT-757 GXII is now a fully functional radio. But, it
took a lot of help from many different people. The saga started with a no power
issue. I needed to build a power cable and that was pretty straight forward.
The local electronics supply store, Texas Electronics, had the parts in stock.
The wiring diagram I found on-line, along with the operator’s manual and a
service manual. Once the power cable was completed, I connected it to the power
supply and the radio, pressed the switch and …nothing happened. I then stated
taking the radio apart, well at least the top cover. This radio was just a
little different than those Motorola Motracs, Maxtracs, Micors and Syntors that
I used to play with. But, I found that the power cable was fine and that there
was power getting to the radio, at least one section of it. I then needed to
see if I could figure out why it was not getting to other parts of the radio.
Google was very helpful. It provided websites like FOXTANGO that dealt with all
kinds of Yaesu radio equipment. There were also Yahoo Groups that provided
insight. I posted on these forums trying to get some idea where to go. I had
determined where the power was and where it was not. I had checked components
in just about every section of the radio. I though that a relay was bad. One
Tuesday night I took the radio, power supply and all the schematics to the LARC
meeting. I had three people, then four people all with years of experience
troubleshooting and repairing radios with their eyes examining the boards, my
findings and making suggestions. It got down to them all agreeing that it was
probably a bad relay. Gary, (Santa), decided that the easiest way to test to
see if the relay was bad was to put a jumper around it. We did that and the
radio came to life. So now it was how do we fix the relay? This radio is 30
years old. Parts, such as this relay, (which looked like a black rectangle)
were no longer manufactured and trying to find one was beyond hopeless. Fortunately,
we found that the black rectangle was actually a box with a lid. We removed the
lid and were able to see the coil and the contacts of the relay. By just
pushing the contacts closed on powerup, everything worked. Well that was enough
for that night. I carefully replaced the top of the radio and put it in a box
and took it home.
At home, the kitchen counter (peninsula) was the best place
to work on the radio. Standing height, two lights overhead, except it got in
the way of kitchen activities. So, further work was moved to the coffee table
in the family room. This meant having a flashlight to see things and working on
my knees or sitting on the floor. I carefully cleaned the contacts in the relay
with alcohol and an emery board. That done, I powered it up and it worked fine,
except that it did not receive anything. It was quiet. I made a wire antenna
and put on it and still nothing. Back to troubleshooting. This went on for
several weeks, then one Tuesday night Gary (Santa), said that he had another
radio that I might be interested in. This one an Icom IC-706 MKIIG. This radio
was smaller, more like a mobile radio, plus it not only covered the HF bands
(160m-6m) it also covered the 2m (VHF) and 70cm (UHF) bands. A great radio.
There was a slight “kicker.” There were three different models of the radio
built. Some did not include the 2m and 70cm bands. Each model had a removable
face plate, so that the face could be mounted remotely from the rest of the
radio. The face plates were interchangeable, to a point. The face plate from a
MKII model would work on the MKIIG, but, it would not display the 70cm
frequencies, or so we thought. The radio that Gary provided was the MKIIG, but
the face plate was from a MKII. After some comparison with a MKIIG with the
proper face plate, and some experimentation, we found that the MKII faceplate
would display the 70cm frequencies, just that instead of being 432.xxx it would
show as 132.xxx. No problem as long as you remember that, and the fact that we
were not licensed in any 132.xxx frequencies.
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