|REED Relays - as used in Ten Tec Argonaut 505s and some other ham equipment
Some notes and correspondence with a ham in USA - noteworthy troubleshooting items
I heard from fellow ham operators that you are very tech savy on Ten Tec radios. I have a 1 owner Argonaut 515 that has very weak receive audio. Even with a signal generator I
don’t hear much and the S meter doesn’t even budge so it indicates that the weak receive is somewhere in the front end.
I know that since I have been an electronic technician for 40 years that all equipment has weaknesses.
I checked all of the voltages on the control board and all are perfect. The TenTec power supply is also putting out 12.8 volts. A little note on that later though.
I was able to send CW and the rig is putting out a few watts as far as I can tell.
Any ideas of a good place to look.? I have cleaned (DeOxit) the switches and pots. The low receive is common on all bands not just one.
I was using the TenTec 12V 1 amp power supply on my KR5 keyer . Something happened and the power supply blew its fuse.
Further checking showed that the MPSU01 transistors had shorted out.
To top it off The Keyer has a reed relay that is welded shut probably from someone using it on a cathode keyed transmitter. Are the relays still available anywhere?
Any ideas or help is appreciated.
K2A** (Identity protected)
*** furthur note from the fellow: The reed relay in the Keyer looks like the same relay that is used in older Argonaut 509’s. The relay has 200 ohms on the coil and is 12 volts
Re: Ten Tec Argonaut 515 has weak receive audio (response from me: Earl VE3AB (Netty Electronics)
I just checked my relays and I only have a few reed relays here and Id like to keep them for projects/repairs I may have.
I do have some surplus GE relays that might be reed relays but the coil is 750 ohm and the voltage is 26.5 v so they might
not work. I do have qty 10 OMRON g6a-234p-st-us12vdc relatively new relays I bought a while back because of this article:
http://www.ad5x.com/images/Articles/QSKBArevA.pdf -- the fellow claims these relays work well in a qsk system. I sell them for
$4.50 each and they might be adapted to your situation. The data sheets are easy to find on line and Mouser likely has them.
Anyways..thats it for now. Ive never had to work on the reed relay except once back in 1974 when I bought my brand new Argonaut
505. The company I bought it off of sent me a new circuit board with the reed relay on it. --73 earl ve3ab (I might go now and look up
reed relays on ebay and see what they have). I might start carrying some for these types of repairs.
|This article is just being written today 2 March 2016 -- article is still in progress
for a few days as I do more research on Reed Relays and in particular, the ones
used in older Argonauts and the older Ten Tec Keyers.
73 Earl VE3AB
I was able to repair the reed part of the relay. I removed the reed switch andI put it through a magnetic coil that I have had for magnetizing screwdrivers. Also called a degaussing coil.
That allowed the reed to go back to the normally open position. Only issue I have with the keyer now is that it looks live a bad 7476 flip flop.
I was also able to get the Argonaut 515 to receive great. I used my scope and found that there was a circuit that was causing a “mute” condition on the audio receive. This was due to
a bad connection in the TenTec Notch filter where it connects to the accessory jack. Everything is running again and that radio has one hot receiver. I only have to realign the VFO as
it is off by 55 KC across all bands.
Thanks for all of your help