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General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc. |
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30th Sep 2021, 6:30 pm | #1 |
Dekatron
Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,953
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It's always the simple things that catch you out.
The little 25-Watt 12V-powered Mirage amplifier I use in the summerhouse to give my 2-Metre handheld a bit more 'oomph' was playing up; though the RX preamp still worked, the RF-sensing part had stopped working so no power-amplification happened.
The changeover relay wasn't changing-over to put the power-stage inline. Brought the amp back down from the summerhouse and tested it in the 'office' - where it worked first time - the relay snapped over cleanly at the first sign of RF at the input, and the output was a good 28 Watts into the dummy load. So, back to the summerhouse, and reconnect. The fault recurred. Grrr!! I was checking out the coax flyleads linking handheld to amp, amp to SWR-meter and SWR-meter to antenna when I noticed that the connection from the solar-panel that keeps the summerhouse battery charged had disconnected itself from. Back down to the office to grab my cheap Chinesuum [£9.99 from Screwfix] DMM, which revealed that the battery was showing about 7 volts. Aha!! No wonder the relays weren't pulling in! Battery has been for a ride in the wheelbarrow and now is repatriated to the office where I'm hoping that my "Sunnpower" 1.5A smart-charger's recovery-mode will get things back to normal. Moral: always check the simple things first, or you will end up looking stupid. |
1st Oct 2021, 9:42 am | #2 |
Octode
Join Date: Jul 2009
Location: Carmel, Llannerchymedd, Anglesey, UK.
Posts: 1,498
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Re: It's always the simple things that catch you out.
You remind me of a transceiver someone asked me to check out, as it would work for a while & then stop. It was only after carrying out long & fruitless checks of the unit that I discovered the fault to be a fuse in the external power line - it was acting as a self-resetting thermal fuse, although being a standard type!
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1st Oct 2021, 1:42 pm | #3 |
Guest
Posts: n/a
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Re: It's always the simple things that catch you out.
Me, setting the current limit too low for a (rather expensive) test. The boss forgave me saying "at least you used the limiter".
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