|Firing up an old rig ? Some tips to avoid seeing smoke.
March 12 2016
One thing not to do is to power it up and try transmitting right off the bat. That would be like staring a car with the gas pedal to the floor.
When you do start to power the radio up..make sure
it is not going to transmit full power. One fellow who wrote me (very recently) started up an FT301 that was sitting dormant for a long
time -- and he had smoke coming out of the lower bottom part of the radio.
-- what you want to do is start out on receive mode only -- and with a fuse in the line of the power going to the transceiver and as well..
it would be a good idea to unbolt the heatsink assembly with the rf power transistors (while testing the radio out initially).. that way..if there
was a short in the final transistors it would not cause a large current surge and smoke !! Also..use a 2 amp slow blow fuse when first starting
out so that the fuse will blow quickly if something is wrong.
Also.. (IMPORTANT) -- make sure all the plug in circuit boards are in the correct spots and not in backwards or out of sequence ect.
This is very important. If you buy a radio and you know nothing much about it -- then make sure the plug in circuit boards (if there are any) are in the
right spots and make sure they are not plugged in backwards.
A little extra preparation work means less smoke or burned circuitry.
BELOW FT301 - BASIC PREPARATION TO TEST -- this applies to other radios as well.
IF you do find someone to work on the FT301s then I can still provide tested parts. -- NOte: I can help you do some primary type of analysis of what is
going on to figure out how much it might cost. -- FOR EXAMPLE..- you can remove the heatsink assembly quite easily. Remove the two coax cables
and label them carefully as to which one is on top and which one beneath. Then jumper the two BNC female connetors with a jumper cable if you
have one or perhaps use wire and then try the radio out as a 10 watt radio. See if there are any problems that way.
Get it working properly at 10 watts then try out the 100 watt module.
When I test out (new to me) radios here.. I use a very good current regulated (current limited) power supply and I check for problems and thus bring
the radio up to power (slowly) and that way no smoke.
|I know that I'm totally out of my league here but I have an old FT-301 D here gathering dust that I'm hoping to get operating again. The last person who
checked this unit out took the crystals out and never return them to me. I would like your thoughts on what it would take and how much it would cost me to
revamp this unit.