Line 6 Spider jam output device type - TDA7????

[Brian Swatton]

I've got one of these on the bench at the moment with a damaged output chip, unfortunately the damage has obscured it's markings. TDA7????

Can anyone tell me what it is?

If anyone has schematics that would be handy too.

[Jazz P Bass]

TDA7293 or TDA7294?
Get the datasheets for both of them.
Osbserve the pinout drawings.
Look for a likeness in the way the IC is hooked up.
The 7294 gets wired a little bit different than the 7293.

[Brian Swatton]

Great, thanks. I'll follow that up in the morning. I thought it was going to be an LM3886 when I first saw it. Shame it's not really as I have one in the drawer.

[Jazz P Bass]

The TDA7294 does not use the 'boot strap' function.
So pin 11 & 12 will not be connected.

[J M Fahey]

How many pins does it have?
Can you measure the +/-V rails?
Obviously with the chip pulled.

[Brian Swatton]

Looks like it's the 7293 as there's a 33uF between p6 and p12. If anyone can provide further confirmation I'd be grateful.

You can see here why I was having trouble identifying. Something tells me this device is faulty.



Thanks again.

[doctor]

Looks like it's the 7293 as there's a 33uF between p6 and p12. If anyone can provide further confirmation I'd be grateful.

You can see here why I was having trouble identifying. Something tells me this device is faulty.

[ATTACH=CONFIG]21059[/ATTACH]

Thanks again.

Low frequency amplifier is TDA7293 and high frequency amplifier is TDA2030A.

[Brian Swatton]

Thank you Doctor, I'll get that ordered.

[mozwell]

line 6 spider 212 & HD75 schematics
spider 212 uses LM3886, HD75 uses TDA7293

[Brian Swatton]

mozwell, you are a star, thank you.

I've got main amp running now, but have now discovered that there is no HF output. The 2030 is fine as I can inject audio direct ok. It looks like Q1 is faulty as I'm measuring about 30R between, what I presume, is b-e.

I was just coming back on to plead for diagrams, so thanks again.

[Brian Swatton]

Ah, neither of those are for this unit unfortunately. No HF amp in the HD75.

[doctor]

Ah, neither of those are for this unit unfortunately. No HF amp in the HD75.

Take that.

[Brian Swatton]

Thanks Doctor, that's the one.

I see now why I didn't read bipolar junctions

[Brian Swatton]

There's no HF drive to the power amp board, I don't suppose you have the other drawings do you Doctor?

Edit: I've traced back past the TL084 on the digital board, it looks like I'm not getting the output from the CS42436 codec.

[Brian Swatton]

Just in case anyone is interested, I eventually resolved the no tweeter output issue.

The guitar signal doesn't get routed to the tweeter, only the Aux/Mic and CD inputs (probably its drums sounds too).

I was suspecting this, and tried to confirm this with Line 6. At first they agreed that this was correct, then after they consulted with someone else, I was told that no, the tweeter should be on all the time.

I've just managed to do some tests on another amp of the same type though, not thought to be faulty at all. This behaves exactly as what I see here, no tweeter output from guitar input, only from other inputs.

So, a lot of wasted time it seems. Sometimes just establishing what correct operation is, is a problem in itself.

I hope that saves someone some trouble anyway.