The Kenwood TM-742E

Kenwood TM-742E
A while back I bought a second hand radio: the Kenwood TM-742E. A great radio with 2m, 70cm and 23cm module!
The man who sold it is a heavy smoker, so I had to clean the rig intensively. But after doing a good job the radio is like brand new. No scratch on it.
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Diamond X-6000

23cm @ PA1JIM

There wasn’t any 23cm ground plane antenna yet on the roof @ PA1JIM headquarters, only the double quad antenna. But the quad is pointing towards the PI6NOS-repeater.
Therefor it was impossible for me to open the 23cm repeaters in Den Haag and Rotterdam. Furthermore I wasn’t fully satisfied about my Diamond X200N for 2m and 70cm. It worked, but not beautifully.
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23cm TRXDid a lot of work the other night at the 23cm trx. Build in the speaker (drilled a lot of holes!) and did the last mod to do more filtering in the VCO voltage. Also fixed the phantom power for the electret microphone. Modulation and LF-sound are now in an acceptable range. There is always room for improvement, but at least I can leave this little puppy running in the background without scaring up every time some one opens the repeater.
Now I have my ‘reference rig’ I found out the filtering of the 23cm TRX is indeed under average. The reference rig can easily hear repeaters from miles away and doesn’t have a S6 to S7 noise without an signal. I think the UMTS-antenna that is about 50 meters away must have something to do with this. I think the next to do for this trx is building a bandpass filter.