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Crate vintage club 20 schematic.

6/12/2000 2:24 AM
Crate vintage club 20 schematic.
Hi I just picked up a crate vintage 20 today. The input jack is broke.Anybody have any advice and schematic would help too. thanks pb.
7/11/2000 8:17 PM

i dont think you need a schematic to change the jack..... but if you find one please send it to me
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7/11/2000 9:16 PM

These plastic nightmares are "Cliff" jacks properly describing the drop off point for the designer. One of the very most common failure points for SLM products. If your amp is out of warranty, replace it with a metal Switchcraft type wired to the PCB. May take some work but I've done it before. Secondly, wire a jumper around the line in/out ahd headphone jacks if you've got 'em (have worked on many VC 30s and up but never a 20) - you can make the jumper where you can restore operation with a simple wire snipping. This way you get the poor jack switch contacts out of the signal path. I do SLM warranty and I've developed a "reliability kit" of modifications that I do for out of warranty amps or where the owner doesn't care about the warranty.  
7/13/2000 5:18 PM
Dave Rich

Graywater, although I'm embarrassed to admit it in this crowd, I have a couple of VC30's and I really like them. Would you mind sharing your reccomendations, tips and tweaks?  
I have a schematic and I don't care about the warranty.  
Dave Rich
7/13/2000 11:48 PM

I have a dim view of the gain structure on channel 2. For an overdrive tone, R59 can be paralleled with a 300k, without pulling the board.  
I deleted a triode on channel 2 and ran into dc blocking. The B+ is too low for what I had in mind.  
I built a pine cabinet for mine. I think I shaved close to 8 lbs off the thing. I put the controls face forward like a fender.
7/14/2000 10:55 AM

Just a quickie right now - gotta head to work. Generally, get all of the Cliff jakcs out of the signal path either by replacing them with Switchcraft or bypassing them. Replace the screen grid limiting resistor (no schematic refrence now) with a larger wattage unit (I often also up the value to 1K depending on the model) - these frequently fail and even on the units where they've upgraded to a 5W resistor the "sandstone" resistors they use still fail - get a good quality industrial resistor. Replace the phase inverter plate load resistors with 1W ones - these fail. Replace the coupling caps around the reverb circuit (sorry to be so non-specific) with "orange drops" or equivalent.  
Like I've said, no "20" experience but on the 30/50 I've added an additional PCB standoff to reduce board flex.  
Of course, being a SLM product, resolder all front panel control and jacks solder pads (have a magnifying glass and an X-acto knife ready for the switches) and also all power supply components - especially the diodes and power resistors.  
May think of somemore but will have to pull the specific schematic and compare it to the rest of the series - oh, these mods are also applicable wo the BV/TV series of amps sans the new standoff.  
Tonewise the VC series has a harsh treble to my ears (strat player) but so far I've not had a customer interested in dealing with it - just the reliability mods (in response to a "down" amp)  
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