Changed antenna, no change in behaviour, so spent 30 minutes sitting on 145.200 after connecting in an in-line power / SWR meter. Thought this was not working as the new vertical showed negligible SWR. The beam showed 1.4:1 so not bad for a start.
Anyway, the rig puts out 12W FM for some time, then it drops to very low power, estimates at < .5W. Back to receive and it is full again, sometimes for a period of minutes, in fact up to 12 till next failure, but sometimes 20 seconds or so. Initial thought is the relay... Back to Castle.
Seems that this cheap rig circa 1980 is going to cost me more than a new modern one.
Thanks Nottingham Amateur, you dodged a bullet which got me right in the bank account.
At what point do I cut my losses?
NOT A HAPPY HAM HERE.
April 2011
Sent rig to Castle again, both relays repaired and now fully functioning except for the memory. Going to get a new rig and keep this as a spare.
It is one of the two relays, if the TX led goes out, then it is the DC changeover relay in the middle of the board, if not the antenna relay.
ReplyDeleteAs far as I know this relay type with on one side closely positioned pins is no longer available anywhere in the world. I solved it by using a simular size but differently positioned pin layout relay UPSIDE DOWN wired using resistor ends to the board, kind of floating. UGLY but it works...
Pedro ON7WP (radio guru)
on7wp@telenet.be
Pedro,
DeleteMany thanks for your comment. I must update the blog as I have had both relays replaced now and no other problems with TX/RX now. The memory function does not work though and I have now bought an ICOM IC706Mk2G for 6m/VHF/UHF.
While I used to build my own ‘valve kit’ and repair/modify the older style of rig, I was a bit scared of doing it myself and disturbing something else which wasn’t so obvious, so it went back to Castle Electronics who again did an excellent job.
I am in the process of moving my blog to my website and will look at updating several sections.
Again thanks for your input
73
Charlie
I reached this post since my dad gifted me his FT after he got tired of trying to get it repaired but noone found the intermittent output problem. I removed the plastic cap of the antenna relay, poured a drop of isopropyl alcohol and slided a very thin piece of paper between the contacts. The paper picked up the carbon deposit on the contacts. I repeated this process 3 times and lastly I poured some more alcohol to clean any possible debris of the paper. I let it sit for a couple hours to dry. I assembled it and works perfectly! no more intermitent issues.
ReplyDeleteJust wanted to post you this note as a thank you for guiding me in the right direction. Cheers from Cordoba, Argentina.