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||Is there any legitimate reason that there
should be a "fresh drinking water" problem on this planet ?
(See bottom of page for suggested answers)
The Radio/Cassette player from hell :
|The phone rang the other
night. It was my
" I’ve got a radio I’d like you to have a look at. "
" It keeps cutting out and I have to push down on a knob to get it to go! "
" Also. It won’t stay on the station. "
So an appointment was made to bring it down to me to “ Have a look at it. ”
The offending piece of equipment was delivered and the “knob” that was causing all of the problems shown to me.
It turned out to be the “mode” switch and it had 3 positions: ' Sleep ', ' Radio ' and ' Tape '.
I had an idea that the switch was faulty or had bad solder connections.
I opened the beast whilst its owner looked on.
No sign of bad solder joints. That meant that the switch was faulty or the solder connections between the sub-board and the main circuit board were the problem.
I intimated that I’d have to pull it all apart to get at the switch.
The radio’s owner then went home with a radio I had lent him.
I wasn’t worried about it being a major job.
The next day I decided to tackle it…
It should only take a few minutes to get the circuit board out and check the soldering… Oh yeah!
There was absolutely no way that circuit board would come out! The dial pointer was stopping it!
The dial cord was attached to the pointer and held in place with 2 bent down tabs and a spot of glue.
I could only just reach down into the bowels of this thing with my finest screwdriver and touch the dial pointer.
There was now way of releasing the dial cord from the pointer that I could see!
In desperation, I found I could lift the circuit board up just enough to undo the dial drum from the tuning capacitor.
I knew the Philips screwdriver in my spectacles repair kit would come in handy one day!
Once the board was out, I determined that the connections between the sub-board and the main one were fine.
That switch had to come out! But to get at the solder joints, the AM ferrite aerial rod had to come out! Whilst looking at this I noticed that the wire that connects to the tuning gang had broken off!
So another fault fixed I thought after reconnecting it! Anyway. The switch was finally removed and checked.
The contact resistance was all over the place so I disassembled the switch, cleaned up the contacts (this was the only option left to me as this horror was about 25 years old!), put it back together and checked that it was now working.
I fixed a bad solder joint on one of the F.M. coils, hoping this was the cause of the unit not staying on the station.
Now I had to tackle the dial mechanism!
After an eternity, I managed to coax the dial pointer out of the front of the unit.
I could now remove it from the dial cord if necessary.
After a lot of mucking about, the dial was restrung.
I then spent hours trying to get the dial pointer to go back into the front of the unit…
No way would it go!
The next day I decided that the pointer had to come off the dial string.
The tabs were unbent, and a drop of Acetone dissolved the glue.
I managed to get the pointer back into the dial scale.
I spent many hours trying to get the dial string to hook up with the pointer.
I finally got it hooked up and I set the pointer so that it covered the entire tuning range.
Now to test the thing!
It worked fine except for one tiny problem!
The tuning was back to front!
A sudden dread came over me…
I had strung the dial cord around the dial drum in the wrong direction! Oh bother! (or some such words)
That meant going through the same time wasting process I had just finished.
At this point, I was VERY tempted to tell the owner that his radio was un-repairable!
The following day I decided to tackle it again.
After many frustrations, I finally got the thing together again.
I checked the tuning.
It was the right way around this time!
I also checked the AFC lock range on F.M. and satisfied myself that it was fine.
Finally I thought it was just a matter of putting the back on and declaring it finished… Oh yeah again!
The back wouldn’t go on properly!
There was a metal bracket which held the power transformer and mains power socket which was stopping it.
I spent ages trying to get this stinking bracket to line up properly.
It also put a lot of pressure on the circuit board and mangled the fuse holder that was mounted close by.
I had really had enough of this radio I thought!
In desperation I removed the transformer and socket from this bracket.
I then mounted the power transformer in the bottom of the cabinet.
There was plenty of room for it to fit.
The power socket was then mounted on the back of the cabinet.
The back then fitted on quite easily.
FINALLY it was finished!
But what an appalling design!
I NEVER want to work on that particular unit again!
If it goes wrong again I’ll fix it alright… With my hammer!
Till next time.
this article belong to "Rick's
Workbench" in Tasmania
: We do not recommend attempting mains powered projects or
The articles from "Rick's Workbench" are for entertaining reading only.
It may be a political farce.
From an early age, (if travelling in the outback
of Australia for example) we are told to extract water from any