Kenwood cable (6 pin DIN & 13 pin DIN) logic levels

The DigiRig site states (Kenwood TS-450 cords for Digirig Mobile – digirig) that the TS-450 cable (6 pin DIN & 13 pin DIN) requires the jumper settings to be configured for RS-232 levels, yet Kenwood’s IF-232C interface manual states that the levels on the 6 pin CAT port are TTL. I presume that the radio is tolerant of +/- 12V yet TTL jumper configuration appears preferable.

Repost from email:

I didn’t get any negative feedback from the operators who ordered TS-480 cables, but looking again at the manuals, you may be correct.

TS-480 manual it shows IF-232C used for the levels conversion:

image.png

The description for IF-232C describes conversion from RS-232 levels to 5V TTL

image.png

Digirig’s TTL is 3.3V, but it crosses the threshold for 5V TTL so that should still work. I would suggest trying default (logic levels) configuration first and if that doesn’t work then RS-232 configuration. Please keep me posted on your results.

I’ve built an interface to go from a CP-2102N Mini EK to the Kenwood 6 pin DIN. It is definitely TTL, NOT RS-232 which could damage the transceiver.
An added difficulty is the TTL signals are inverted. As if that wasn’t enough, the Kenwoods can have voltage spikes. I burned up a few 74LS04s learning this. I ended up using a 74LS06. There is 5V available from the radio for the pull up. A similar circuit would be needed for your product.
Bill KC7I