Blown RX-5650

Hi guys, I wish I was joining this site just to enjoy my new box, but unfortunately it didn't last one day in my possession. Thats quite the start eh?


I picked up this little guy while in Japan visiting my partners family. Her mother actually bought it new back in the day and it has sat in a closet for most of that time. After admiring it for some time they insisted I take it home, much to the confusion of my partner who cant understand why I would want an old stereo . It is not missing any knobs or parts and there are no scratches or cracks. We played a cassette over there so everything works great, until I got it home.

After only an hour sleep on the plane and rushing home to try it out, I completely forgot to use a travel converter to go from 240V to 100V. All i heard was the transformer buzz, a small click as the safety switch for the power outlets cut off and that was it. Now even with the inverter it wont turn on.

Hoping those crafty Japanese has installed an inline fuse somewhere I opened it up to check the damage.





Without really knowing what Im looking at, the power board seems OK with no scorch marks on the resistors. The transformer though was very hot and there was faint scorch marks from where it attaches to the frame.

My question is, with my limited knowledge in electronics, the higher voltage has probably fried the transformer, and thats what needs to be replaced? Would this be an easy job for a repairer, and is it possible to convert it to 240V instead on replacing it with another 100V?

Any help would be appreciated as I have really learned my lesson here, now I get to stare at it and feel horrible until it gets fixed. :'-(

I hope someone here can help Tentacle Party. It's a lovely radio that is worth getting fixed!

Great to see another .au dude on boomboxery too, welcome aboard!



Rock On.

hey friend, i guess you must have burned the transformer,

BUT

there must be some kind of fuse somewhere

even though someone may have bypassed one, there are usualy more than one.

and if so / when fixed , it must run on batteries.

then you must fix another or that transformer!!!

nothing much.

output voltage on those transformers is pretty much the same

in, 110 or 220,

out , arount 13.8v

keep atention to size, and overall outupt needed current ( A ).

cheerio and welcome aboard.

btw , i think, one of the fuses is inside that small plastic box / cover

that you took a photo of.

Welcome aboard, Tentacle Party!

A lot of power transformers are fitted with an internal thermal fuse that becomes an open circuit when a certain temperature is exceeded. Once the thermal fuse opens, the transformer is trashed. You'll need a new transformer.

Hopefully the boombox was powered off when you plugged it in which would limit the problem to the power board and not the mainboard. Your power supply does not seem to have a fuse. Many fuses are installed optionally and yours does not seem to have it. In any event, replaceable fuses are usually on the secondary side and not the primary, which is what is connected to your mains. A new transformer sounds to be in order (at the very least) and possibly the rectifier diodes too. While you are at it, you should install a 240 transformer instead of a 100v one. It might even be smaller which would be a big plus for you.

BTW, does it work on batteries? If not, that could mean bigger issues than just a transformer.

Thanks for the info guys. It all doesn't seem so dire now, just a case of hunting down parts and buying them. I will get some batteries this weekend to test if it still works that way. I fear that the system may have been on when it was plugged in as the Power LED was lit for the few seconds of its tortured new life.

If I'm to look for a replacement transformer what are the specs i should look for. The 100V 10A 21VA on the original doesn't seem to match what i can find on parts-express and the like.

OK. It looks like 10v and not 10A. Seems kind of low -- is this a 6 cell boombox? So it sounds like you need a transformer with 230/240 volt primary (115/230 dual voltage works too) 10V secondary and approx 2A secondaries.

If so, try this:

http://mouser.com/ProductDetail/Tri...EpiMZZMv4oUrzpPKU3O%2bui9ulA%2bFlomI7LJR/Ags=

Just make sure the measurements will work. Also, make sure that the secondaries are connected in parallel and not series (or prepare for blowed up episode #2, this time definitely on main board).

I'm pretty sure it's a 10 cell as I took them out for the plane trip and they looked like they had been in there for 20 years

When you say secondaries, you mean the output? That site is great, and it's even Australian, thanks heaps! They even have an awesome datasheet for that transformer, with jumper instructions for wiring to parallel.

I have experience with car stereos but i might source the parts and get someone a little more experinced in the dark arts of soldering to help me out. Especially with the diodes.

If it's 10 cells, then 10volts is too low. Perhaps it's wired in series? That would give it 20 volts output. I would rather look for something that closely matches your dry cell voltage so if you have 10 cells, that would make power requirements 15 volts. While 15 volt transformers are available, 16 volt tranformers are probably more common. Anyhow, transformers often (but not always) have dual secondaries (outputs) so if you wire them in parallel, you will double the output current (amps) but if you wire them in series, you will double the voltage but the amps are halved. In any event, the VA remains the same but voltage is not your friend because too much and things go poof. High current capability is not a problem because the boombox will only consume as much current as it needs and no more.

Most 15 volt boomboxes will read 18-19 volts at the transformer when powered by mains. Just FYI.

She works with batteries! No main board damage, oh she sounds so glorious! Wait, is it bad to refer to them as she?

And sorry Superduper it only takes 8 batteries, so that's more inline with the original 10V transformer i guess? So now I'm looking for a 12V transformer?

12v (12.6, etc) = easy to find transformer. Make sure you read spec sheet. Make sure you hook up in manner that will supply aprox 12 volts out with approx 2 amps.

Hey Tent, awesome that she runs on batteries.

Best of luck with the fix, would be keen to know how you go converting to 240v.

Rocking Box!

Yay! Glad to hear that the 5650 is not totally dead.

Good luck with the transformer repair!

Thanks guys, it has certainly lived the high nicotine lifestyle in Japan so I spent all night scrubbing it down with detergent and windex. It looks so much better now all clean, I will post some pics tomorrow!

welcome to the site and that is an excellent box you have there i have the panny 5600 which looks simular,, well looks like a transformer is in order and everything else is looking good

If you have trouble finding a suitable transformer, LMK. I think I have that exact same transformer here someplace so you can keep the box 100% original.

Does that box have a 12 volt input anywhere?? maybe you can use an external transformer.
Welcome aboard and Im happy your box is not totally toast.
BTW windex is a big nono Never use harsh chemicals to clean plastics.
Mild dish soap water will clean the dirtiest nicotine stained boxes you ever seen.
Good luck getting her right.

I thought windex was ok for everything? Thanks for the tip though, I won't use it again! But I guess it's lucky, I used it at first but it didn't clean the grime off at all, thats when I changed to the dish soap and a soft sponge. That worked a treat.

Is there a way to clean the woofer or at least blacken it a little?

And you are right, it does have a 12V input. Either way I would like to replace the internal one as I will bug me if i know it's broken, and by my hand!

tentacle Party said:

Is there a way to clean the woofer or at least blacken it a little?

Click to expand...

Hey TP, you might want to have a look at this thread:

viewtopic.php?f=2&t=4473