I have a Kustom 1-B chassis (which I think is a bass amp), that has been hacked into. It is missing the speaker jack and the wires that served the jack. It doesn't appear to have anything else done to it. The problem is that I don't see where the speaker leads originated. In searching the site (and the schematics link) I don't see any available schematics for this model. Does anyone happen to know if any other models would have a related circuit which I could use as a guide in getting this thing up and running??
Sorry, I don't have the serial number handy right now. It is called a "Kustom I" on the front panel, model 1-B (from the badge on the back panel). The controls are Vol, Bass, Mid, Treble (with pull for Bright). I seem to recall it was a Bass amp (1x15 combo) which was used by my band in high school for a PA. Needless to say, it was not appropriate for a PA, but it was best that we were not heard anyway. Somehow I ended up with it in my parent's attic and I have no idea who butchered it up.
stevem Messages: 4733 Registered: June 2004 Location: NY
Senior Member
Well I guess its not a vintage tuck n roll coverd kustom.I went to the broadway music site and they to do not have schematics for this model, so it must be a pretty late one.On all of these solid state amps the output jack can just be grounded to the chassie if the common connection between the two main power supply filters goes to ground,youcan check this with a ohm meter.
For the hot speaker lead, if the amp has a recording output jack feed by one resistor, than hooking up your hot lead to the input side of that dropping resistor should do the trick.Its worth trying and will not hurt the amp if it doesn`t work.
The definative way to find the hot out would be to find the common junction of the 2 or 4 output transistor emitter resistors, as this is where the hot side output comes from.
The emitter resistors would most likly be 3 to 5 watt wire wound types and would be of a value of .51 ohms to 1 ohm.
If you are not a tech, than a decent tech should beable to figure this out.If you do find the locations I am talking about here, before you hook it up to a speaker, put a volt meter across the jack set for 100 volts DC. If you turn the amp on and see anything more than a constant 1 volt on the meter than the amp has a problem.
This test will keep you from blowing your speaker(s)
That is great - thanks for the info. I'll see if I can track down the parts and get this baby up and running. I did find a schematic for it last night at site. $20 is possibly worth it, being that there may be more wrong to the amp than just the cut speaker leads, but I will certainly use your roadmap first.
stevem Messages: 4733 Registered: June 2004 Location: NY
Senior Member
I hope it turns out to be an easy fix, but the first thing to do would be to check its fuse, if its bad theres not sence in stuffing the jack in until you find out why the old fuse blew.
Smoke1 Messages: 107 Registered: September 2003 Location: Southern Maryland Solomon...
Senior Member
You are in luck I have a complete very good operational 74' 1-B amp head only thing missing is a couple of knobs because I also have a Complete 1977 I-B in a very good condition cabinet. Email me at Smokemcnasty@Hotmail.com if you want to see pics and if your interested in buying this amp Cheap. I don't need it anymore since I got the better complete one this year. And No, Even Kustom Dan hasn't been able to find the schematics for these I asked the same question last year Feb 05! If your interested in getting this head. I have also cleaned it up and installed a new 2o FT grounded power cord. It's only 25 Watts but it pushes a 15 incher very loud.
It's a 1974 Kustom 1 Bass Amp Model 1-B, PN: 200-0305-00, SN: 112390 , 25 Watts RMS
Smoke1
Smoke1 Plays Kustom Amps & Old Tube Amps Loud in S. Maryland