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eHam Forums => Long Wave / Medium Wave => Topic started by: KM1H on May 24, 2020, 03:55:32 PM

Title: Modifying Kenwood TS-940 and TS-950SD to TX on 660M
Post by: KM1H on May 24, 2020, 03:55:32 PM
By this I mean transmit (full transceive as the RX works fine there) at the low milliwatt level out of the transverter port where it would be amplified and filtered. This Class A signal does not go thru the driver and final circuits.

Carl
Title: Re: Modifying Kenwood TS-940 and TS-950SD to TX on 660M
Post by: KD6VXI on May 24, 2020, 06:46:41 PM
By this I mean transmit (full transceive as the RX works fine there) at the low milliwatt level out of the transverter port where it would be amplified and filtered. This Class A signal does not go thru the driver and final circuits.

Carl

Carl,

Not sure of the topology of those radios, as I don't have one.

However, the TS440, of which I'm very familiar with, you have two places to make sure you're general coverage covers //everything//.

Their is the diode you must clip for MARS/CAP as well as a pin on the microprocessor that is programmed. 

I was able to lift that pin and enable TX in the AM broadcast band and below.

It's been //years// since I did that mod.  I'd have to go to the service manual since the radio is packed up in the C-Train now. 

However, it IS possible to get the older kenwoods of the TS440 / TS940 era to TX outside the stanndard MARS/CAP regions.

Since the 440S didn't have a transverter port, I dunno about that.  The 440S would drop power fairly quick when it came to going to the AM broadcast band.  I believe the most I was able to get at 800 khz was about 20 watts, peak.

Hope that helps.  I was able to find the pin to lift and reprogram via the service manual.


--Shane
KD6VXI