The GF-9595H Voltage Outputs + 1 More Photo!

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Ghettoboom767

Member (SA)
Hi everyone that's been helping me-Here is my voltages from the transformer and to part of the voltage wheel.
I also have included 1 more photo so you can see exactly what is what.

Here it is:
There is 2 wires coming from the transformer that went(They are cut and go no where now) to the voltage wheel (you can see them right here in the photo)
There is 70 volts a.c. coming out of these 2 wires.
There really is no voltage at the voltage wheel(only 1 terminal is connected still(there's 2 wires connected to 1 terminal-that's it.)
The voltage at at posts of the voltage wheel-.5 volts is all.
The output wires from the transformer(2 red wires going to power supply board)-voltage is only 7.3 volts-under load with cassette running-7.1 volts.
This seems low,shouldn't it be 12?
BTW-there is supposed to be a switch above the voltage wheel-is it the dc/ac switch-doesn't work on batteries-This is missing or what is ist that went there?
So 1 more thing underneath or should I say on topof the transformer there is a thing that is above that's small silver rectangular box thing and at 2 of it's posts it puts out 9 volts ac and when i switched it to test in ac it's 20 volts-I'm not sure on this thing.
But I had to post this as I forgot to do this.
Any help would be great-Also the transformer has some letters on it here it is:
P0645AF
12 W9ZD

Again this thing works but get's distorted under load and with he caseete on it slows down with volume quite noticebly and sounds not to good especially the cassette.The radio can go pretty loud but again lights go out under load-bad output it must be??!!

I wonder if the transformer is bad?
It doesn't get warm either.
Have a good weekend-GB.


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GF-9595H8.jpg
 

Superduper

Moderator
Staff member
It's hooked up wrong.

That is a multi-voltage transformer. The primary has multiple connection points and depending upon how it's hooked up, will result in different voltages observed at the secondary.

My suggestion: Disconnect the secondary wires and hook them up to voltmeter. Then try various combinations of the primary hookups and observe the voltage output on the meter. Be careful when working with A/C. When you get something that resembles what you expect it to be (approx 12v for 8-D cells and 15v for 10-D cells) then you've got it hooked up correctly. Sounds like it's hooked up expecting 220 volts A/C. Keep in mind that the actual voltage is usually several volts higher than battery voltage so an output at the secondary of 13 or 14 volts is probably correct for an 8-cell boombox.

When you've got it correct, then hook the secondary wires back up.
 

Ghettoboom767

Member (SA)
Hi SD-I'll try that-It's a 10 cell which would be 15 volts but like I said the 2 red wires going to the power supply board are only at 7.3 volts-how is this thing working even??
I'm going to test the voltage at the motor for the cassette deck also and check that.

I would really like to just get a different good transformer and a new voltage wheel-then I know it would be good.

I still have a question: What went above the voltage wheel?? I'm thinking it may have been a ac/dc switch??
If anyone has one of these or a similar model that has this kind of a voltage wheel and a switch above it-let me know or show me a photo please!!


Thanks again SD.I'll give you my outcome in a couple of days when I get this all tested out.
I appreciate all of your help.
I really like the 9595-advanced for it's day and draws 40 watts-no weakling here!!
I love the digital display.
Have a great weekend-GB. :-)
 

Ghettoboom767

Member (SA)
Hi SD & everyone-I tested the connection at the cassette motor.14volts ac///7 volts ac.
I'm assuming the voltage is ac because it's only operating on ac(doesn't work on batteries).
This would be about right thinking it's a 15 volt motor?? But there is no load when the speakers aren't connected??True?
The speed of the motor is slowed down when the volume goes up.Can't test voltage w/drain right now.
I just wanted to know what voltage was going to the cassette motor.

But yes I believe the transformer is wired screwy(I didn't do it!).I bought it from henry(Hong kong).I knew it needed work-good deal on it.
I'm thinking new transformer & voltage wheel and switch would be hopefully be a good start.
Anyone got any of these parts??
I'd love to just start with some of these parts and wire em' in.

I don't know about wiring the old transformer up any differently because of the couple of melted areas that wires burned a little area(must have been crossed or something?).
So I'm hesitant to hook up this with the current transformer any differently.
I have to ask Henry a couple of questions and see if he remembers anything.
Thanks guys-I do appreciate your help-GB. :-)
 

Superduper

Moderator
Staff member
Well, for what it's worth, I bought a few things from Henry and at least one had very poor work previously performed. I knew also that it needed work but now I have a very expensive parts box since it's not repairable. But I digress.

The voltage wheel for your box -- forget it. Those parts aren't going to be available new any more. For one, it's probably going to be an import model which means parts were probably never available domestically to begin with. Add the obsolescence factor and unless you can find someone willing to part out, it's gonna be "no deal." Again, forget the voltage wheel. Just bypass it. Take the terminals from the A/C jack and connect it directly to the transformer.

The voltage that you are measuring at the motor is DC, not AC. There should be a bridge rectifier in the power supply section that rectifies the A/C to D/C and everything in your boombox is going to be D/C. Technically, I should say powered by DC since the audio signal is going to be AC but forget about this because this will just make it more complicated for you to understand. Anyhow, the voltage that you are measuring at the motor is not important. Unless you are suspecting the motor or control circuit, it's much more meaningful to measure the voltage at the power supply output.

As for needing new transformer, all I can say is whoa!, slow down. If you are getting power from the transformer, it's doubtful that your transformer is bad. Usually, when they go bad, they go waaaay bad.

So, going back to the beginning....
(1) measure voltage from the secondary windings of the transformer. This voltage will be A/C. If this voltage is low (again, A/C) then the primary windings are hooked up wrong. Try hooking the A/C cord to different leads until you get the proper voltage at the secondary leads.

Once you get this fixed......... then
(2) measure voltage at the power supply out. This will be AFTER the rectifier and typically will be the leads that go to the main PC board (when there is a separate power supply board). If your rectifier is constructed using 4 diodes, you should check them using the diode test function of your multi-meter.

Only if and when you've figured out these 2 things, we can move on to other things. Hopefully, verifying and correcting any issues here will fix your problem without the need to go further.
 

Superduper

Moderator
Staff member
OK, didn't see the part about the burned wired before posting. If the primary wires look like they are sort of melted due to poor previous soldering or something, the transformer should be Ok and the other wires should be OK to connect as long as they are properly insulated afterwards, preferably with quality shrink tubing.

If the voltage wheel had an excessive amount of corrossion, it could have introduced an unacceptable amount of resistance into the circuit. Resistance has a side effect of creating heat. With 120volts, it could be A LOT of heat which could have melted the plastic in that area. If that is what you are talking about, the transformer should be no problem. As long as the primary windings look serviceable, then you should be OK. Once you find the combination that works, you should solder and then heat shrink the wires. Don't do any funky "me-technician" retrofits by twist tying and electrical taping (or worse).

On the other hand, IF the melted wires look like it's due to heat from the transformer windings, then perhaps you'll be better off with a new transformer. Partially shorted windings will affect the output, although I doubt that this is the case. The picture is not too clear but I don't see any physical signs of such although anything is possible.
 

Ghettoboom767

Member (SA)
Hi SD-Thanks so much-I will do that later this week.I will keep the boombox from getting current from the transformer while I do this? I'm assuming that in case I touch the wrong 2 wires in checking voltage.
I'm pretty old school and limited in tech but i do understand what your saying.
Test all the voltages coming from the output of the transformer.
Also am I looking for 110 or 14-15 volts? Is this all in DC even coming from the transformer(example-the 2 cut wires that have 70 volts ac?.I don't believe it registered in dc at that those 2 wires.
Once again I'll do this and I was thinking the same thing-bypassing the voltage wheel.

Let me know what I'm looking for coming out of this transformer.if you could.It doesn't say voltage anywhere on it
Remember then there is the 2 small wires that go into the power supply board and those are at 7.3 volts.
I hope I haven't confused you any-just giving you all the info I have..
I should have more info by Th. or friday-busy week ahead.
Thanks again & have a super week-GB. :-)
 

Superduper

Moderator
Staff member
BG. No, I am not confused. I think it is the other way around. I am a little concerned because based on some comments you are making, I don't think you have a good grasp of electronic basics, without which this may be too much for you to handle. It's not hard but you do need to know the difference between AC and DC.

From the wall, you are going to get AC. It's always going to be AC until the electricity gets rectified (or converted) to DC at the power supply rectifier, which typically is an array of 4 diodes. From that point on, it should be DC.

Disconnecting the transformer to the boombox is a good idea however, I doubt that there is any way you can hook it up to get higher than intended voltage at the secondary. I don't have time right now but when I get a chance, I'll see if i can find a diagram that show you a multi-winding transformer and then it may become easier for you to understand.

As for voltage, you don't need to look for 110. That is the voltage you are going to see from the wall. Once it inputs the transformer, it will "step down" to a lower voltage at the secondary. The voltage at the secondary (the other half, that goes to towards the boombox. This is the only voltage that will be important to you. You don't need to measure any voltage on the primary side. The 2 wire combination you choose to connect to the A/C (wall) will dictate what voltage you get at the secondary. Again, the secondary is what is important and that is what you should focus on.

Now, I can't stress enough how important it is to choose the correct current type on your multimeter. If you choose incorrectly, the reading will not be right and you will only confuse yourself more. Both the direct in/out to the transformer should be A/C. It won't be DC until it is rectified. In fact, transformers don't even work when connected to a DC current.
 

Ghettoboom767

Member (SA)
Hi SD-Ok I'm understanding what your saying now,
I'll be testing this and I'll let you know.
I hate it when people cut stuff off and take things off-it does kind of confuse the next guy!
Thanks again SD-GB. :-) :yes:
 

Prime

Member (SA)
Hey Jeff, just check my earlier posts on what to do. SuperDuper, I believe
your making this far more difficult than what it really is. I've watched this thread
and the previous one take way too many tangents instead of focusing on what
needs to be done. Its just a radio fix, not a course on basic electronics. ;-)

We do not know if the voltage selector is bad. I've never had one go bad, so...

Jeff, try reconnecting the two wires back to the voltage selector to obtain the
correct voltage(13-16vdc) across the large cap next to the four diodes.
 

Ghettoboom767

Member (SA)
Hi Prime-I'll do that tomorrow or Wed.
I've been super busy but by Thursday-I'll give you my results.
Thanks again-I appreciate it!
GB. :-)
 

Superduper

Moderator
Staff member
Sorry guys. With all that was going on with this box, didn't know a simple way to explain "how do I fix this."

Think I'll stay out of this for awhile.
 

monchito

Boomus Fidelis
well i belive super duper i understood everything you had said and probably for us working on the box ourselfs would have been a different story , but sometimes it gets a bit hard trying to explain with all the details but when things like this come up you have to take it one step at a time,, it could be anything how about like a box that i plugged the ac cord in the backlight turned on but the radio did not turn on as soon as i pressed the power cable a bit it came on ,,see sometimes small things like that are the things like can ruin a good day , and then you get boxes thats been worked on which sometimes have been rigged, so with that said its sometimes hard to tell exactly what the problem might be..and remember some i mean some might turn on even on 220 if plugged in 110 some boxes act totaly dead which is ok because it not in the correct line but i have seen boxes still turn on on 110v with the switch put in 220 radio might work cassette most of the time will be dead,, so yes with what sd said is correct and what prime said i agree to but the real thing to look at here is that we do not have the box in front of us and its going to be gb the one to figure this out i belive the info is there and if the person working has little background in electronics then it would be a bit harder to try to explain and the person to understand what to look for, hopefully gb can find the problem with the help given here.......... :yes: :yes:
 

Superduper

Moderator
Staff member
Thanks Monchito. :yes:

:huh: I see a pic with what looks like a corroded voltage selector.
:huh: There clearly were modifications and the wires were cut -- this leads me to suspect the voltage wheel is bad.
:huh: GB mentions that he sees melted wires -- there is a reason for that -- I offered possibilities.
:huh: GB is having suspicious voltage measurements and comments that he thinks voltage at motor is A/C leading me to suspect that perhaps he didn't understand the difference and/or why it would be DC instead of A/C.
:huh: The questions is "HOW DO I FIX THIS?"

Somehow, after all this, I have my doubts why re-connecting the voltage wheel will fix everything. The clues (above) makes it difficult for my brain to accept that as a likely fix. I'd admit that sometimes, people have a tendency to overthink things and I'm one of that crowd. However, experience is a great educator and I rely heavily on my teacher, even though she sometimes does get it wrong from time to time. :lol:

So.... a simple one line answer that will fix this is beyond my language abilities.
 

monchito

Boomus Fidelis
and really that what it looks like the board looks like its been worked on before not sure that that transformer is the one that came with that box and the wheel is really just to connect 2 wires together which could be eliminated altogether and left direct has we use 110v oh and btw please make sure that the dc scale is used on the multimeter instead of ac :lol: :lol: it happens also :lol: :lol: especialy when measuring voltage on the circuit board or cassette motor :yes: :yes:
 

Superduper

Moderator
Staff member
monchito said:
and really that what it looks like the board looks like its been worked on before not sure that that transformer is the one that came with that box and the wheel is really just to connect 2 wires together which could be eliminated altogether and left direct has we use 110v oh and btw please make sure that the dc scale is used on the multimeter instead of ac :lol: :lol: it happens also :lol: :lol: especialy when measuring voltage on the circuit board or cassette motor :yes: :yes:
:agree: :agree: :agree: Oh Wait..... I think I said all that already so I'm also agreeing with myself! :yes:
 
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