My amp is getting power, I can see the fan turn on by the transistors but I'm not getting power to the board with the input and potentiometers are. I'm thinking it's the power connection to that board. What should i look for with a multimeter and so on. Thanks
A NAME might help?
a model even.
Whatever it is see if you can find a schematic on the net as that will speed up replies.
Cheers, Phil.
Trace Elliot gp12 Smx..... The model number is 122hsmx. I'll try to find a schematic.
I couldn't find the exact schematic but I found one close. I measured to see if I'm getting power to my preamp board and I'm not, the connector to the preamp is coming from the transformer. Any suggestions?
Post a link so we all speak about the same.
http://www.eserviceinfo.com/downloadsm/58490/Trace%20Elliot_GP12.html
This is the best one I found
I'd be searching on the board for *IC 11 and 12* and see if you have voltage on pin 3 of both. If you have a stable Pos/Neg reading their then maybe check cables and other connections.
Surprising that most electrical problems I find are related to connections.
Phil.
I can't find ic11 or 12. I found ic1 - 9 though. The only bad coonections I found were the ones to the speaker out, but it doesn't explain why my preamp board is getting power. I tested the power connected to the pre amp board but it's not picking up any voltage.
IC11 /12 are in the Power Supply.
They are Voltage Regulators and *look* like 3 leg mid power plastic transistors.
Thet are labelled 7805 and 7905.
And the PCB silkscreen *should* call them IC11 and 12.
Now go find them and measure voltage on each one's leg 3.
Get their datasheets both to see their physical aspect and which one is leg 3.
Please be careful with *how* you write things, you seem to imply the opposite or a very different thing, it's confusing for us.
We may guess what you mean, and guess wrong.
Examples:
Quotebut it doesn't explain why my preamp board is getting power.
I guess you mean: "is
not getting power"
Or am I missing something?
QuoteI tested the power connected to the pre amp board but it's not picking up any voltage.
"the power" ... what?
Power supply or power amp?
And, what does "
picking up any voltage" mean?
You have a
power supply there which
supplies voltage ... or not.
The preamp will "pick up" voltage if it's present, will not if not.
So you must check that those voltages are available.
Good luck.
Sorry about being unclear, auto correct kills me. I'm testing them in a few.
Sorry, didn't mean to sound rough, but some statements were confusing or contradictory.
Hard to help you that way.
Are you google translating or something similar?
It sure muddies meaning :(
Hey guys, I tested the output from the transformer and found voltage. I can't remember how much but it did shock me lol. I will post a link with the correct preamp schematic. (the other one was the wrong model) Anyways there are zero ohm resistors on the preamp board ( it calls them zero links on the schematic) and there was one missing where it is printed on the board saying stereo. So I just put a wire there since that's basically what those resistors are since they have no resistance but still no luck. If I need to explain better let me know, thanks for all the help for a newbie.
Here is the link.
http://72.233.80.90/download.php?fileid=51859
Oh and btw I'm posting from an iPad, so sometimes it will change my words.
1) As of the IPad thing, I turned autocorrection/ITap/intelligent_keyboard etc. off in every mentally retarded device I own (such as so called "smart" phones) because it drives me crazy. Prefer to hit each key 3 times if necessary but it writes what *I* want.
2)
QuoteAnyways there are zero ohm resistors on the preamp board ( it calls them zero links on the schematic) and there was one missing where it is printed on the board saying stereo. So I just put a wire there since that's basically what those resistors are since they have no resistance but still no luck.
Pull that link which does not belong in there and will only confuse things.
If they didn't fit it , it's because it's not needed.
The link was there but it broke off. I just saw the metal part that you solder in the pcb holes. If I was looking to see why my board isn't turning on but it is getting power, what should I start looking for? Something near the power connection? And what?
Have you tried to get a signal out of efx send into another Amplifier?
This is a rather complex setup and for those starting out it might prove difficult to fix even with the schematic.
You have 3 voltages in that thing and one is High voltage for the Valve.
So be very careful as even 150 Volts can kill you.
You really need to establish those psu voltages and find all the points they travel too.
Phil.
I can try that, It wont be till late tonight. I have to play upright bass tonight for a jazz gig. Lol.... I'll send a message after I try it. Thanks for all the help!