Hang in there bud 

Don't give up before the miracle 

If anybody can get your amp running these guys can.

Maybe post up some pics of the boards

 

Well, I've replaced T1 and T2 as well as D1. Still reading pretty much the same voltages. At this point, all transistors have been replaced in the amplifier portion. I hate to deem this unit a loss but I am leaning that way as it was quite a mess with the traces from prior techs. Im 99% sure I have all the traces repaired correctly.

Its Alive! Built a box for and am really happy about it. Works with a small Accutronics plastic reverb tank, still sounds deeeeeeeep.

Quote from: saturated on April 21, 2024, 03:07:37 PMGood afternoon solid state afficianados.

Hope your weekend is going well at least what's left of it.



I had a question about preparing some banana jack patch cable connectors whether or not these needed to be soldered.

The wires shown are not gonna be used they are only to illustrate the routing of the holes in the metal part.


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Maybe I just strip the wire insert it and screw the cap down...idk

Thanks

Use the compression screw on system for now and decide later on after pondering it a bit if you think soldering will be the best final path. As an electrical/electronics engineer, the "right" way of doing things is not always the best or most rational, and primarily taught for what you should expect if you go to work in whatever cornered field of science your education leads you to where far more educated and experienced engineers told me over a decade ago, you'll ultimately end up only using 10-15% of your education wherever it is you settle in lol.

I'm sitting on a huge regret ATM from trying to repair my Zoom G5 some lunatic woman smashed and doing it the "right" way was a disaster! I suspect my repairs won't be successful but fortunately, the unit overall should still work and I will either have to scroll effects to a different bay of the controls since it has 4 and 2 were broken, or stick to programming it by USB and PC.
The only upside to the destruction of that unit is I bought a 2nd one. I got the damn thing 12 years ago brand new when they were about $450, but for $180 on zZounds which a week later, went right back to the normal price. I have some current generation digital floor units that are absolutely amazing, but this 12 year old dinosaur still outperforms them tonally. Parameter wise, the modulation and effect parameter adjustable functions are quite mediocre.

Good afternoon solid state afficianados.

Hope your weekend is going well at least what's left of it.



I had a question about preparing some banana jack patch cable connectors whether or not these needed to be soldered.

The wires shown are not gonna be used they are only to illustrate the routing of the holes in the metal part.


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Maybe I just strip the wire insert it and screw the cap down...idk

Thanks

I'm relieved that my signal generator provided some nice traces

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Idk why the trace from that transformer was so sketchy.

Yes sir thank you 

I decided to take a look at this on my scope

Btw here is the source of 12v ac

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So connecting scope probes directly to cables coming from ac source

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My phone was struggling to get a full trace left to right despite trying to adjust trigger etc the trace was jittery and flickering real bad

So now connect scope probes to (+) and scope ground to (-)

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Which I like that but when I had the scope switched to ac I had just a flat line

Then connecting scope probe to (~)

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So I guess everything is cool. 

I'm off to connect some other stuff to the scope and try to get a better full steady trace.

 

I think you have your AC source there hooked up to the output pins.
The error when installed backwards would have reversed the + and - output pins.  The AC would have still been correct as it is non-polar.

I bought a Crate GX1200H and 4x12 cabinet for $150 off Craigslist yesterday evening. I was surfing for used table saws, and I don't know how, but I ended up in their music gear ads. 

The stock speakers in the cabinet are definitely lower quality in comparison to those in the GX combo I bought, and it needs some modifications to both the clean and dirty channel tone stacks, but I don't think I've come across a deal this good in a few years.
The main problem with the stock speakers is their low end response is abysmal, mids and treble are crisp and punchy; great for numetal. The more you crank the volume, the more aggressive in reduction on your bass control is required, and even at modest volumes, it has to be significantly cut from the start.

Unfortunately, I remember why I had to mod this head extensively when I bought one 28 years ago which I still have to this day, but fortunately after some proper education, the mods I have for them today are exponentially superior. The lead/rhythm EQ has a shape control which has some great characteristics, but it won't produce a significant scoop as many of us desire. Fortunately, it only involves replacing a 100 ohm resistor to ground with a 500 ohm pot. The clean is great but needs a brightness switch added which will actually be there to shunt some of the highs to ground. The dirty EQ could use a bit larger value cap, but overall, it's primary shortcoming is they opted to save money by excluding the midrange control, adding the shape which is a bandpass sweep, and then reintroduced the mid in some of the models that came quite a few years later, another of which I own.

As far as solid-state goes, the GLX version is identical but with the mid control included and the best solid-state amp I've ever heard for metal. I think because they introduced the Blue Voodoo when these came out, they intentionally shot this model line in the foot by ditching the mid control. These sold new as full stacks for 650 to $800 depending on when you went looking for one, and I think the Blue Voodoo head in itself was 8 to $900. The simple solution back in the day was running an EQ on it's effects loop, but even that they required a stereo Y-adapter to presumably, save more money on mfr. On my original, I scrapped that and converted it to 2 mono jacks on the rear which eliminating the front stereo 1/4" jack gives an odd location but ideal space for adding the dirty midrange.

If I knew near 30 years ago what I did today, I would have made a killing modding these even for solo shredding metalheads, and they wouldn't have such a very checkered reputation like they do to this very day. This model line and those it was reintroduced as with all the same short comings are pretty much considered the worst solid stamp of the 90's onward well into the 2000's lol.

I decided to put a load on it...12k ohm resistor

Similar results

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More Bruce

 

I have a feeling Bruce says we need some capaci-taters