FT-857D
My old transceiver, which is 20 years old, is sick. The reason for this is age, operation in an SUV, on the street in summer and winter!
PROBLEM:
1.The shorter the band, the less power transmitted.
And at a band of 160 meters it completely disappeared.
2.When receiving on bands, if (IPO) or (ATT) is not turned on, there is no reception. That is, if you do not enable one of these functions, there is no reception, only silence.
Solution to these problems:
1.
- It was identified that the relay RL3002 switching contacts are completely closed (stuck);
- and also the relay RL3005 and RL3007switching contacts also do not switch to the closed position;
- as well as relay RL3008 and RL3015 switching contacts periodically sticking
All these components have been replaced with new ones:
RL3002, RL3005, RL3007 - G5V-1-2 DC12 (Mouser No:653-G5V-1-2DC12)
RL3008, RL3015 - DS1E-S-DC12V (Mouser No:769-DS1E-S-DC12V)
Solution to these problems:
2.
-It was discovered that the transformer T1007 was damaged. The case was broken off from the board and was held on only by two soldered wires out of five. Possibly damaged due to shaking while driving off-road.
I restored this part by hand, rewound it with a new wire and soldered it, then secured it with glue.
After this repair my transceiver FT-857D started working like new again!!!
