Originally this video was to be about replacing the Omron LZN4 relay on the IF board of a Kenwood TS-130S amateur radio transceiver to fix the "desense" problem on switching from transmit to receive.
On many older Kenwood transceivers like the TS-130S, the relays get a bit manky with oxidation and stop working properly. A symptom of this is when you switch from "Send" to "Receive" the transceiver's sensitivity drops drastically, and might simply drop out for no reason even if you're not sending. It's a very frustrating problem, and one that many people have dealt with.
The consensus is that this is almost always a problem with the IF relay that switches from Send to Receive, located on the IF board. Also there can be problems wit the RF attenuator relay, which can cause similar symptoms. I had already replaced the RF attenuator relay before this point (link below).
Unfortunately, after successfully replacing the relay on the IF board... it turns out that wasn't the issue with this radio! So, the video will follow the additional steps I took to find and diagnose the issue, and how I got it sorted. It was frustrating, but I learned a lot, and that's the important thing in the end.
The relay in question is an Omron 12V DPDT relay, which was discontinued. For a time the Matsushita N4FB was available as a drop-in replacement, but it is also discontinued.
Previous video replacing the RF attenuator relay: • EHV #4- Replacing the ...
This site: www.k4eaa.com/... sells a drop-in replacement that fits in the same space but uses two SPDT relays. This is not an endorsement of their product, but if you need to replace the relay(s) in your Kenwood, it seems like a good replacement that doesn't involve sourcing really hard to find parts.
You can find the Kenwood TS-130S Service Manual (and other manuals for it) here: rigreference.c...
24 авг 2024