One thing in what we do is we have to keep our wits when doing simple things like not thinking and connecting the wrong power supply to whatever.
The Decade CM-10 needs positive center polarity. I have several adaptors and picked a 12 volt one but the one I picked is the only one I have with center negative(didn't even know I had it) as all others are the norm center positive. When it didn't work I wondered why. It just worked the other day.
So I checked the outlet and yes 120 volts so then checked the adaptor and saw center negative on the multimeter.....oh oh! Got another power supply and no go. done!
See what happens....whatever you are powering, make sure before you connect power to it it's the right adaptor and correct polarity. Even with a portable radio...make sure you have the battery polarity right!
Keep you wits about you with your transmitters, and processors, especially the Procaster, Rangemaster, you know the expensive ones. And processing gear like the Schlockwood. Wrong polarity no good! CM-10 ready for the garbage.
I'm not sure. But there maybe a diode that blows to protect the unit from being fried. I've had a lot of electronics that have had a protection diode built to protect from such.
Unrelated but how come I don't get a reply thingy to click on to reply directly to the person that posted originally? Instead having to reply by comment.
Try opening the unit and search for tiny fuse . Look for tiny paper clip size hole on the outside of unit ,for reset. I did the same thing to one of my scanner radios. There was a reset and after pushing paper clip in the hole ,it worked again.
One time I put fresh AA batteries in my TECSUN PL-310 Radio but it wouldn't work, so I double-checked and one of the batteries was put in backwards. "Yikes!", I thought. When I corrected the situation the radio worked, but I've always wondered if something was permanently damaged.
@wefr To directly reply there is an arrow at the bottom of the post. Click on that and a direct reply like I just did here will show in the next reply
space.
As for the CM-10 there is no protecting diode but 3 surface mount 100uF caps right off the power jack on the board. Electrolytics don't like wrong polarity even for a minute. I will try to remove those off the board and solder regular ones to the contacts on the board. But not easy like through hole components. But wrong polarity is a killer for other things like ICs transistors etc.
@1620am-w9xaz No reset. This is a CZH-05B transmitter that was modified for Decade to meet the Canadian regs with BETS.
@carl-blare You were lucky. An electrolytic capacitor the wrong way will be done almost instantly. There may have been a protecting diode for inadvertent wrong battery placement. ICs and transistors get ruined with wrong polarity.
@mark Now there is an arrow. earlier there was not one. Okay no diode I don't know then. Caps don't protect, They're cooked. you may be lucky if the damage stopped at the caps.
@wefr All I can do is replace 5 caps and if still doesn't work it's garbage. Hard to replace those as they are small surface mounts 100uF and may ruin it trying to remove those. Not like through hole normal components. Will try replacing with regular caps on top of board.
What we know.
My understanding is that electrolytic capacitors may not fail instantly if subjected to flipped polarity DC, but are put under thermal stress when this happens and may continue to operate for an unpredictable length of time, may suffer from shifted values but still function, or may explode.
Solid states devices, like transistors and ICs, burn out right away.
At a 100 kW FM I worked for, one day a loud bang issued from the equipment rack. The engineer found that the manufacturer had installed a large capacitor with reversed polarity and one day it blew up after operating for a long time.
But maybe I have it wrong. It's time to see what YouTube videos have to say on the subject. If I find anything I'll link it here.
Well, that's that. Garbage. Replaced 6 100uF caps but I knew I was wasting my time.
Watch that polarity guys! One mistake can ruin anything fast.
@mark Sorry to Hear Mark. I was hoping for a better outcome. And yes make sure everything is connected properly before applying power.
@carl-blare I had a capacitor blow on an 50 year old radio component receiver... Like you said... Major pop sound ,then smoke but not fire. It was a large capacitor to the power section of the receiver.
I also have a Procaster AM transmitter and a while back(not using it now as I am on FM) I connected a power supply that the Decade MS-100 uses which is AC 16 volts...not DC, to the Procaster which should get 12-15 volts DC to the studio to power it and didn't realize till a day later BUT....it worked beautifully! Better than before! How I don't know. It shouldn't have. No humming or anything in the audio. When I saw this I had a "heart attack" and me and Gerry, the owner at Procaster could not figure out why as it shouldn't have worked and most likely should have destroyed it. Really lucked out there! Didn't have to replace a $700 transmitter. But it worked so well that I thought of using 16 volts AC for it all the time.
Go figure!