Mains TX outputs for Line 6 Spider 4 anyone?

[allante666]

I will have to reverse enginer it 52Bill. As I say Ill draw it out on paper but it realyl is a very basic circuit and I get the impression that when I see it in diagram form Im gonna say 'Is that all it is?' but it just makes it hard to see when its on a crowded double sided pcb with most of the tracks covered by the smoothing caps and then a load of signal tracks mixed in for good measure. Job for monday morning now methinks!

[allante666]

Ok, so I had a bit of a scribble and drew the basic part of this circuit out on paper which I will attach. The diodes which are in the lower voltage part of this are in fact bog standard rectifier diodes (1N4007 equivalents) so that rules out Zeners. Im still going with my theory that the secondary winding is tapped off centre and has a high voltage and low voltage half. I will of course stand corrected if anyone can tell me otherwise. And yes Im still waiting for Line6 to get back with a price.
So, anyone have any thoughs on these secondaries? Someone did say they thought, but werent sure, that the two big caps each had 43 volts on them but they were going from memory so wouldnt guarantee that.

[g1]

Your drawing does not seem to match the board.
You show 3 wires from TX connecting to a 5 pin connector. Please specify which pins are unused.

[allante666]

The drawing is correct, the five pin connector only uses the three pins Ive shown it connected to. The one which appears to have the diode connected to it carries on through to the other side of the board and joins the other diode as in the drawing.

[g1]

Does your TX have the same type connectors at both sides like this?


If so, the 3 wire connector is the primary, not the secondary.
If yours looks different, please post pictures of the TX and it's connectors.

You said some of the TX's have 3 wire secondary, but I don't know where you got that info. All of them have 3 wire primaries.

[allante666]

D'y know what? You might have a point. Im going on how it was connected when it came in. The five wire was connected to the three pins on the primary side and vice versa. Im now wondering if he had had a play around. Nothing looked out of place and with it having two alternate plugs for input voltages I just assumed (yes, I know what 'Assume' does!) it had two windings in the primary. leave that with me, Ill have a look tomorrow and see what happens!

[g1]

Sorry I missed that first time I looked at the pic. Most manufacturers would never use the same connector on both sides like that. Big no-no.

[allante666]

Well hats off to you sir you saw wood where I only saw trees! I snuck a look tonight and yes, it was the wrong way round. The connectors are interchangeable and apparently he had let his 'techs have a look' before he brought it in (he's in the Air force).
Anyway it brings it back now to its original reported fault of no audio. And yet again Im struggling to find a schematic which matches this one! It works if you play into the mp3 input so the power amp is fine. No audio from guitar and nothing out the headphones. Im wondering if this guitar sense circuit is faulty but this one doesnt match any dagrams! It has a little breakaway board with the input jack on it but its not like the one in the diagram I have. My little board has U14 on it and U1 on the 'user interface board'. I have 5 wires from the input jack board where the diagram i have shows 10 etc. I have 10 between th eower supply board and the ui board but the diagram shows 12. Mine is a Spider 4 75 watt, fairly new if anyone has any ideas?

[52 Bill]

Now I'm totally confused, unlike my normal hazy state. I thought that the original problem was that the primary winding of the power transformer was open and we were trying to help you figure out a replacement.

[allante666]

Ah Bill do keep up! Yes, thats what I thought but after g1 correctly pointed out that the primary and secondary connectors were reversed, the tx is working fine. It measured o/c because i was measuring two differetn windings! 80% my fault and 20% the customers I think. Anyway, he had said its original fault was no audio before the tx 'fault' which appears to have been his 'techs' having a quick look and taking some measurements and putting it back together the wrong way round. In fairness its not hard to do as both connectors are the same.

[Jazz P Bass]

Here is the preamp schematic that covers the Spider IV 30 & 75 watt amps.

Does the volume effect the MP input?

If so, the schematic is labeled weird. (IN L & R / RIN+ & LIN+) at ic U2.

Line 6 Spider IV 3012 Schematic and BOM.zip

Make sure the TP_GTR_SNS goes high when a cord is plugged in to the input jack.
The jack holds it low when no cord is inserted.

[allante666]

Thats the schematic im using but its different to this amp. This does have a small breakaway board with the guitar jack on it like the diagram but theres a little preamp on my board which is U14 but in the diagram its U1. Also the MP3 input is on the user interface board. I did have a look for the guitar sense test point but couldnt see it. Attached is a pic of mine if it helps shed any light.
And the master volume alters the mp3 volume if that s what you mean?

[olddawg]

Have you done as Bill suggested and looked for a thermal fuse in the open primary winding? Usually you just cut the paper with some cuticle scissors and it's right there. Solder in a pigtail fuse with some heat shrink. Wrap it with tape.

[allante666]

olddawg Ive digressed a bit now, sorted the tx thanks to g1 and am now on to a no audio issue!

[Enzo]

I just opened the drawing Jazz posted of the Spider 4. The breakaway board has an IC which is U14, not U1, as far as I can see.

Whatever number the IC is, does it put signal on the connector to the main board? Does the IC have power at its corner pins?

The MP3 input bypasses all the digital stuff, it goes directly to the master volume stage. So if you get MP3 but no main input sound, the trouble is in the digital or before.

Do you have the big IC AK4552? Iif so, are the input signals reaching pins 1 and 2 of it? And does it spit out signal at pin 15 and 16? Is TP_LOUT and TP_ROUT marked on the board? And are there signals there other than MP3?