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Messages - g1

#1
According to the board layout, it should be squeezed in between the relay and the big cap, probably under the wire.
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#2
Yes.  Decepticonned.   :)
That is a single 12VAC winding, with 2 sets of jacks.
But you need a center-tapped winding (6-0-6 or 12-0-12 VAC).
If there were 2 there you could have run them in series to make the 12-0-12 which is probably what you were thinking of.

You could use a couple wall-wart adaptors but you need AC and they are usually DC.
#3
Yes, DC volts to ground.
Good luck to Utah in the NHL game Tues. (old Jets vs new Jets).  :)
#4
Sometimes, as the voltage is being brought up with variac, there will be current at various voltages just due to variance in the supply rails as they are coming up.
So, if you are bringing it up at different speed than you did last time, you may not get glow where you did previously, or vice versa.
I guess you are still showing -20VDC at output?
Next step would be to record DC voltages for E,B, and C of transistors in power amp section (Q8 thru Q16).
#5
If you get a glow now, that's good and means the bulb limiter is working.  Not sure why some people recommend high wattage bulbs, it defeats the whole purpose.  I think maybe they are wanting to actually use the working unit at higher power levels, which is not necessary.  It should only be used for troubleshooting at idle conditions.

Original untouched photos would be more helpful.  I can't read backwards  ;) and would like to see both sides of the board with no editing and no tape on it.

P.S.  what is saving things from burning up right now is that there is no load connected to the output.  With the big bulb, if a load had been connected there would have been smoke and sorrow again .
Very important for solid-state amps to not connect a load until everything is working right with no load (exceptions are so rare, not worth discussing here).
#6
You should be using a low power incandescent bulb like 40 or 50W.  A big wattage bulb will not light up or offer much protection.  If anything is warming up, you should be at least be seeing a glow.
Otherwise I suspect the lamp limiter may not be wired up right.  Maybe try it with some other household appliance to see if it lights up.

I am looking at your pictures and at the supplied schematic and I can't find any spot that I think correlates to the orange wire in that connector.
This makes me think the schematic is not a good match which really complicates things.
#7
The Newcomer's Forum / Re: The Edsyn SoldaPullt
October 30, 2024, 09:10:56 PM
The tips are teflon I believe, they are high temp but they do melt and wear out.  Replacements are available.
I've been using the solda-pullts forever, but recently bought a different brand with a high-temp silicone tip.  The difference was amazing, the flexible tip molds to the work area so you get a big boost in the amount of vacuum.
But it's just silicone tubing at the tip, so it would be possible to get some that would fit the solda-pullt.  Just needs to be high temp stuff, I think 400 deg C.
#8
The cap was ok.  The soot on it is from some other part nearby that burnt, maybe replaced previously.  Probably that NTE brand power resistor near the cap.
The trace was not broken, it was burnt. That would be where the smoke came from.  What does it connect to, a transistor?  Which one?
Where did you get 2N5484 Fets from?  They are obsolete so there are probably lots of fakes out there.
#9
The Newcomer's Forum / Re: Possible ripple sighting
October 29, 2024, 09:18:27 PM
I take it that the 'normal' outs have higher current capability?
The ripple is kind of odd looking, is it giving the correct DC voltage?
#10
Amplifier Discussion / Re: Rickenbacker TR35b project
October 29, 2024, 09:14:32 PM
Quote from: agdrago on October 29, 2024, 04:11:35 PMif there is anyone locally
Here in Tuktoyaktuk ?  ;) You have no location listed in your profile.
You said that in order to use a recommended substitute, you would have to do a major re-design, why is that?
Not everyone has time to watch an hour long youtube video, tell us what the 'similar solution' is.
#11
Not sure what the 'current state' is.  Seems we have gone back and forth a bit on whether the output transistors are installed.
There is a sticky post regarding 'lightbulb limiters'.  You should read it and build one, it will help protect from damage during repairs.
https://www.ssguitar.com/index.php?topic=2093.0
#12
Cooling is never a bad thing.  Capacitor failure is a way higher percentage of faults in the modern era, and it is mostly caused by heat.
#13
Quote from: saturated on October 27, 2024, 09:22:47 PMSorry forgot to add that stuff that looks like copper braid is some kinda fiber or paper (insulation?)
Ok, that makes more sense, my mistake thinking it was shielding.  So you have a nice 20 ft. 16ga. speaker cable for PA usage, or you could make several 3 ft. head-to-cab spkr. cables for guitar rig usage.

Also, spkr. cable is usually more expensive than instrument cable, so someone might even trade with you.
#14
I just realized the thread title is probably taken from what is written on the cable itself, DOH!
So it is speaker cable, but seems to be a bit odd type that also has a shield.  If so it could be used as instrument cable if you connect the shield at both ends.
#15
One meter probe (black) to chassis, one meter probe (red) to the 'tip' connection of the output jack.  Set meter to DC volts, then check again with meter set to AC volts.