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Transformer identification resources(Line6 spider III)anyone got info on these?

Started by Zappacat, August 03, 2009, 12:54:25 AM

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f_b_ilies

I think I have some good news. I bought the 300W 220/110 transformer and the amp works fine on headphones. The chassis/speaker is with my uncle, going to retrieve it asap. At least I know the effects are OK.

Btw, the 220/110 transformer doesn't have grounding, is that OK?

phatt

Quote from: f_b_ilies on June 15, 2010, 09:49:16 AM

Btw, the 220/110 transformer doesn't have grounding, is that OK?

Primary ground?
             I believe that one has already been answered. 8|
CT of the *secondary* is normally used as the *Common* node.
Phil.

f_b_ilies

Got that, but I meant the transformer's power cord and the wall plug. Same for the 110 output, it has only 2 holes. So when I plug the amp's power cord into the transformer, the ground pin just hangs in the air. I was expecting it to have a dummy ground wire between input and output, bypassing the actual transformer, just to provide grounding for the amp.

phatt

Then you need to FIX it!!!  :trouble
The incoming Ground wire should be *Bolted* (with the proper washer and lock nut) to the Metal Chassis of the Amp.
Drill a new hole if need be but *failure to Ground the Amp* might be the last mistake you ever make 0:)

While we are on the subject;
Don't tie any in coming *Mains wiring* to low voltage or signal wires.
Keep Mains seperated from all the other stuff.
The reason should be obvious 8|
Phil.

J M Fahey

I get what you mean.
You may add a ground lug under any screw which touches the chassis and use a long wire, with a crocodile on each end, and ground your amp anywhere available, such as a cold water tap.
The other (better) option would be to build a dedicated power strip, with the 220/110 transformer mounted on a piece of plywood, with a 3 prong cable that goes into the wall and a 3 hole socket for your amp, where the ground connection goes straight through, skipping the transformer.
You should also match neutral to neutral.
Both hots won't be directly connected, being that one is 110V and the other 220V.
If my explanation sounds confusing, tell me and I'll draw a wiring diagram for you.

f_b_ilies

Quote from: J M Fahey on June 15, 2010, 11:22:32 AM
I get what you mean.
You may add a ground lug under any screw which touches the chassis and use a long wire, with a crocodile on each end, and ground your amp anywhere available, such as a cold water tap.
The other (better) option would be to build a dedicated power strip, with the 220/110 transformer mounted on a piece of plywood, with a 3 prong cable that goes into the wall and a 3 hole socket for your amp, where the ground connection goes straight through, skipping the transformer.
You should also match neutral to neutral.
Both hots won't be directly connected, being that one is 110V and the other 220V.
If my explanation sounds confusing, tell me and I'll draw a wiring diagram for you.

I think I got it. The main idea, in simple words: I need to drive the amp's power chord ground prong into the wall socket's ground, right? All this with proper 3 prong/hole cable/socket

J M Fahey

Yes, you have to provide a "copper path" from the amp's ground to the wall socket ground, irrespective of what the other two pins see.
Easy to check: after witing *do not* plug nothing into the wall outlet, and confirm with your multimeter that the chassis ground actually has direct continuity to the male power ground and has no continuity whatsoever to any of the two other pins.

f_b_ilies

Too happy too soon. The amp part is dead after all. There is a continuous hum in the speaker, that doesn't change when I turn the volume knob. It doesn't go off when I connect the headphones either, allthough that is suppose to mute the speaker. The headphones output works fine though, no hum in the headphones. My uncle is looking into it. The amp board is fairly simple, there are only a few parts on it and they seem replaceable. It doesn't show in the pics sent earlier, cause it's a bit hidden and I didn't notice it. I'll keep you posted.

J M Fahey

Well, if the preamp/digital stuff  is alive, good for you, that's the unrepairable part (not even at the factory)
If the power amp is dead, it can be either repaired or , worst case, replaced.

f_b_ilies

One step further. The TDA you mentioned before was actually hidden behind a cover that was pushing it towards the radiator. After taking that off, the root cause became visible quite spectacularly. We saw that it's a TDA7293 and it's all smoked and has a few pins completely burned off, see pics. My uncle then measured the voltage between pins 13 and 15 according to the TDA datasheet below:

http://www.datasheetcatalog.org/datasheet/SGSThomsonMicroelectronics/mXrqwxu.pdf

He got about 75VDC there and concluded that probably everything is alright up to that point. After taking off the board he measured all the capacitors as well and there was still electricity in them, so they probably survived as well. The only thing I'm worried about is the other small chip CTS0814, it has some smoke on the pins, but it's probably from the TDA blow.

Now I'm debating wheter to replace the TDA or the whole board. Seems equally difficult, cause the wire stripe is soldered directly to the board as well, it doesn't have a connector. I think I'll just find someone to replace the TDA first, since we don't have the proper tools. Then worst case, I'll go back to Line6 for a board. Wonder how much they will charge?

My uncle also said we could also replace with a TDA7294 (he actually has one at home), saying that it pretty much does the same thing as the 7293, but it's more resistant and can take higher voltages. Just in case I didn't learn my lesson.  :duh

bry melvin

that "other chip" is a resistor network
http://www.mouser.com/ProductDetail/CTS/767163203GP/?qs=hbgUSdfWRJVF%2fMAjWsBsKQ%3d%3d
here is its Mouser page:


its part number is the top one 767163203GP  CTS is the manufacturer te rest is likely date codes

J M Fahey

Hi fbillies.
Your amp can be repaired, so PLEASE do not destroy it by trying.
Work slowly.
To begin with, if you can not reolace the ribbon wire, much less you can replace the chip.
1) Although they are almost twin brothers, replace the 7293 by the same code.
2) Thouse are ttrough hole plated, dual side boards, VERY easy to damage.
Get a *GOOD* soldering iron, around 4W; a *GOOD* solder sucker, some desoldering braid. You need those holes clean of solder before pulling the power chip.
Anyway, since it is already dead and no Terminator, cut all pins beforehand, close to the plastic body (and far from the board) so you can remove them one by one.CAREFULLY
3) Clean old grease, put new one plus a new mica insulator and mount tightly but not crushing it.
*Then* solder it to the board.
Use a lamp bulb limiter the first time, it's quite possible that the amp works at once.
Good luck.

f_b_ilies

I took it to a professional. He replaced the TDA and saw a broken track underneath. He fixed it with a wire. We turned it on, smoke and sparks again around the TDA. Then we noticed another broken track, it's actually visible in the last picture above, on the right side of the resistor. We fixed that one too, turned it on, no smoke anymore, just a loud pulsing hum in the speaker. It was late Saturday afternoon, the shop was closing, so now I'm waiting for further troubleshooting.

J M Fahey

Quotesmoke and sparks again
I guess you did not use a lamp limiter .
Work relaxed and unhurried, check everything twice, by going slow you are actually saving time.
Also remember to start testing the amplifier *no load*, no speaker attached, until you are sure you have no DC on the output.
Besides that, *now* you know why "Late Friday Jobs" have such a bad reputation.
Don't pester the guy when "he's closing the shop", wait until Monday (or whenever he can do it)

teemuk

Do the higher power Spiders have a switch mode power supply? If yes, then light bulb limiter might not work with them and some alternatives are needed.

But if you can use one, definitely do so.