Sunday, March 25, 2012

standard c828m


I bought this radio on a hamfest. It was realy cheap, just 10 euro's. I was told that it still worked.It does not look verry pretty But what can you expect for 10 euro.

Well it did work. The transmitter worked quite well. Output was down to 5 Watts so I realigned it a bit. Now the output is 8 watts. I could get a bit more but then the harmonics are to strong.
All 12 xtal positions were filled. That is a nice bonus. It has some simplex channels , some repeater channels and 144.800.

The receiver had problem, it was deaf. It needed 50 uV for a readable signal.
I found out that the pre amplifier transistor had been replaced by a bf??? I tried to find out what the original transistor should be. Finally I found the manual at mods.dk. The transistor should have been a 2sk19. I had no such device in the junkbox so I tried something else. It turned out that the j310 could be used as  well. Now the sensitivit is ok. It needs 0.3uV for a readable signal. This is acceptable.