Sunday, July 3, 2016

Icom IC-730 repaired ( counterfeit 2SC1945 drivers)

Some years ago i aquired an Icom IC-730 from an estate.
This transceiver came with original manual, serv. manual and invoice included.
It had 2 major issues; no rf power and on-off switch was not working.
An evening measuring on the final boards with Theo PA0KN concluded defective driver stage.
Other challenge is to find a spare on-off button.
I ordered 2 new 2SC1945 and a 2SC1971 at a French Ebay seller, this to be sure i would receive no fake parts.....
For several reasons the transceiver was put on the shelf and ten months later the new parts where put in the final stage of the IC-730.
Unfortunately still no rf power....strange because all transistors measured okay...
We removed the new 1945 transistors and test them with a component tester....bingo... they where fake! Counterfeits with another pin layout. Also the 2SC1971 was fake...
Ofcourse i contacted ebay seller BIANCAS66. He told me that i was the only customer who encountered problems and that his parts where real... Sure! I asked him to solve this issue but he refused. So stay away from this French cheater!!!
I was able to buy some new 2SC1945 here in the Netherlands for a fair price. These where real and after putting them in, the IC-730 came to live with 100 watts of power.

The only thing to do was to replace the power button.
A couple of months ago i found one on a dutch selling site for a very low price.
Paid and got it the other day. Looked and worked okay, time to replace the broken one.

It's a lot of work to get access to this knob. But when you remove the frontpannel and loose the screws off the frame you can remove the mode switch and unmount the power switch. Take the new switch, fix it with the 2 screws and mount all back in reverse order.

After 2 years a complete and 100% working IC-730.
Note that frontpannel and knobs are not placed yet.

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