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Some questions [message #10326]

Sat, 24 January 2009 00:43

SKEETER
Messages: 9
Registered: January 2009

Junior Member

I am new here, this is a great site. I am an old dude, been playing for 44 years and remember when Kustoms were the hottest thing going. If you didn't have at least one Kustom stack in your band you didn't get the gig at the local swimming pool.

I just picked up a very nice K150-2, I am working on a blues album and wanted it for the tremelo and vibrato as well as the beefy tone and I have many questions.
First, this one has a serial number in the series 84XXX. Judging by other info I have seen here I am wondering if this is a later model, it seems like a high number. Does anyone have an idea of when it is made?
The reason I am concerned about the age is because I want to put a new lamp in it (which is not functioning) and I would like to know if the lamp replacement info applies to all years.
This model also has a polarity switch that looks just like the power switch. Does it contain a lamp also?
When I open it up to change the lamp, is it pretty much self explanatory or is there a trick or two to getting it out? From the front it looks like a sealed switch with a lamp in it, but from the posts I have seen here, I get the impression that the square blue button is not part of the switch. Is this right? Is the lamp socket replaceable?

Also, I intend to take the head out of the cabinet and build a new cabinet for it and store original to keep it intact. It is nearly new looking, no sense in me tearing it up gigging.
Is there any reason not to do this?

Lastly, I have never seen an XLR plug with 4 pins. It seems I read somewhere here that it is for switching 4 different fuctions. Is it a monmentary switch or does it have to continiuosly complete a circuit?
I am only interested in being able to switch the tremelo , is there any reason not to drill a hole in the back panel and put in a 1/4" jack and connect it to the appropriate lug on the XLR?

And, do you know what the pinout of the XLR is?

Thank you in advance for any info you can give me.

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Re: Some questions [message #10327 is a reply to message #10326]

Sat, 24 January 2009 11:25

LesS
Messages: 478
Registered: December 2002

Senior Member

Hi SKEETER,
K150-2‘s were made May 1971 to Dec 1973 – yours (SN 84xxx) was made May 1972.

For a K150-2, the replacement bulb is GE335, which is 28 volts at 40ma. The bulb screws in. The polarity switch and power switch both use the same GE335 bulb.

To install using a small hose, see SteveM’s comments near the bottom of this post:
“Re: K-250-4 export models”.
Myself, I prefer to remove the switch (you have the remove the amp from the cabinet).

I would recommend using the Kustom for gigging as is - instead of building a cabinet. It’s fun taking Kustoms out in public. Just get a cover for it to protect it.

For the 4-pin jack, I believe that each pin is shorted out to turn on each effect.
Until someone else posts telling you the pin-out pattern, you could just try shorting each pin to see what effect each pin controls. (EDIT - do not short the pins! see SteveM's posting below.)
The switch you need is not a momentary switch.

-Les S

[Updated on: Mon, 26 January 2009 12:30]

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Re: Some questions [message #10331 is a reply to message #10327]

Sat, 24 January 2009 19:26

SKEETER
Messages: 9
Registered: January 2009

Junior Member

Thank you, your response helps a lot.
I have a multiple purpose for building a cabinet.
I want to put handles on it so I can handle it easier.
I do a lot of gigging at times and I want to preserve the original cabinet.
And, I intend to make a cabinet that is light weight, something I have devised for speaker cabs.
And, I want to make it smaller, which the tuck and roll does take up a little more room.
I am getting old and I am a bit disabled so light and easy to carry is important to me.
I build a lot of my own gear, so it is not a big deal for me to put something together.
But being as Kustoms are a bit of a horse of a different breed and I have never owned one before now and have not worked on them, I am not sure what to expect inside.

Knowing it is not a momentary switch helps a lot.

[Updated on: Sat, 24 January 2009 19:29]

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Re: Some questions [message #10335 is a reply to message #10326]

Mon, 26 January 2009 06:22

stevem
Messages: 4775
Registered: June 2004
Location: NY

Senior Member

Hi SKETTER and welcome.
With the k150 k200b and k250 serise of amps you only need a foot switch to turn off the effect.
I can send you a 4 pin xlr, then all you need is a 2 button foot switch and I can tell you how to wire it, or if need be take it to a repair shop to get it wired.
Antique electronics and Mojotone both stock many different 2 button types. You can even use a slavaged one that has LED indicators in it.
At the main listing/forum section of the board if you click on the commecnt section and then open the posting for K250 export, near the bottom of that posting you will see where I gave info on bulb replacement.
I you get really stuck on the foot switch thing if you send it to me I can wire it for you.

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Re: Some questions [message #10336 is a reply to message #10335]

Mon, 26 January 2009 10:50

SKEETER
Messages: 9
Registered: January 2009

Junior Member

stevem wrote on Mon, 26 January 2009 06:22

Hi SKETTER and welcome.
With the k150 k200b and k250 serise of amps you only need a foot switch to turn off the effect.
I can send you a 4 pin xlr, then all you need is a 2 button foot switch and I can tell you how to wire it, or if need be take it to a repair shop to get it wired.
Antique electronics and Mojotone both stock many different 2 button types. You can even use a slavaged one that has LED indicators in it.
At the main listing/forum section of the board if you click on the commecnt section and then open the posting for K250 export, near the bottom of that posting you will see where I gave info on bulb replacement.
I you get really stuck on the foot switch thing if you send it to me I can wire it for you.

None of that is a problem for me to do, I repair most of the gear in the bands I play in.
I would like to have the right XLR and will pay you for one if we can arrange that.
I am in central Ohio.
I have to order one of the bulbs for the lamp too. If you have any of those it would be worth my while just to get what I need from you.

I have foot switches around here I can alter or I can build one.
Do you know if there is a separate switch for the trem and the vibrato, or are they both activated by the same pin?
Thanks for your response.

[Updated on: Mon, 26 January 2009 10:51]

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Re: Some questions [message #10337 is a reply to message #10326]

Mon, 26 January 2009 12:26

stevem
Messages: 4775
Registered: June 2004
Location: NY

Senior Member

No, both trem and vibrato are on the same switch.
Here is some info for the pin out of the xlr.
pin 1 = ground
2 = 12 volt dc power for LEDs so do not short this to ground in trying to test the pins!
3 and 4 reverb and trem/vib, I forget which is which so you will just have to try it.
Since you have to order bulbs from a parts house they may also stock a 4 pin male xlr, if not give me your ship to adress and I can get you out one on the week end.

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Re: Some questions [message #10338 is a reply to message #10337]

Mon, 26 January 2009 14:39

SKEETER
Messages: 9
Registered: January 2009

Junior Member

Thanks for telling me about the #2 pin, I would probably have just tried shunting them each to ground to figure out which is which *yikes*.
I might still just put a 1/4 " jack in and be done with it. I will never need a foot switch for anything other than trem. That would make it compatable with all my other stuff.
Is that #2 pin hot all the time?

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Re: Some questions [message #10350 is a reply to message #10326]

Tue, 27 January 2009 06:27

stevem
Messages: 4775
Registered: June 2004
Location: NY

Senior Member

Yes its hot all the time!
What I would do to keep the value of the amp up would be to get the 4 pin male XLR and make a short adp cable to take you from the XLR to a 1/4" female, in this way if you ever sell the amp the new owner would have the stock XLR workable for a foot switch.

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Re: Some questions [message #10352 is a reply to message #10350]

Tue, 27 January 2009 10:44

SKEETER
Messages: 9
Registered: January 2009

Junior Member

I can't imagine that adding a 1/4" jack on the back would change the value much. I only paid 150 for it, and although I take care of things and want to try to keep the material nice I am not that concerned about the value. I wanted it it for the tone and to use. As big as the thing is I am thinking there is likely to be places on the back ( unless it is layed out differently than most amps) that I can find enough clear space for a jack. I do that kind of stuff quite neatly. I can make it look stock.
although the adapter is a good idea.
I will have to wait until I take the head out to see.

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Re: Some questions [message #10353 is a reply to message #10352]

Tue, 27 January 2009 11:12

chicagobill
Messages: 2006
Registered: April 2003

Senior Member

I believe that the reverb tank mounts on the back wall of the chassis, so there isn't a lot of room available for adding a jack.

For what it's worth, I would recommend removing the xlr jack from the back of the amp and cut a small metal adapter plate that can be held in place with the original screws, right in the same original holes. That way there are no permanent changes made to the amp.

I would then take the xlr jack, place it in a plastic string pack and securely tape it inside the chassis, out of the way so it could be replaced at a later date. If you do this make a little drawing showing how the original wiring was done and keep it in the pack with the old jack.

Just a second opinion.

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Re: Some questions [message #10354 is a reply to message #10353]

Tue, 27 January 2009 11:24

SKEETER
Messages: 9
Registered: January 2009

Junior Member

Thanks that is a good idea.
I could also take the line out jack out and leave it lay inside with shrink wrap around it and just put the switch jack there.
But I have enough machining tools here that making an adapter in the 4 pin jack hole would probably be quite easy. I wouldn't even remove the jack. I could just insulate it and leave it attached to something inside of the amp with a cable tie.
I have some large shrink tubing here that would probably fit over the XLR.
I am assuming that the common on the jack is chasis ground.

I noticed that the verb tank is VERY sensitive to amp shock, much more so than most. Does it have any kind of bushings on the mounting screws? I was considering trying to do something about that while I am in it as well.

[Updated on: Tue, 27 January 2009 11:26]

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Re: Some questions [message #10355 is a reply to message #10354]

Tue, 27 January 2009 12:16

stevem
Messages: 4775
Registered: June 2004
Location: NY

Senior Member

with the twist lock these amps have for the verb I have found there is a couple of things that happen.
1) The foam pad on the face of the lock falls off and rubs on the pan springs.
2) The long term use of the lock streches out the springs so that the smallest vibration will cause them to make noise.

3) The pan is mounted to the inside wall of the head with rubber stand offs that dry rot with age, and cause the pan to dangle an be more sensivtive to vibrations.

To dismount these pans the nuts on the rear of the amp must come off which can be a problem due to the rubber mount spinning. I wound up making a square notch tool out of a long flat section of aluminum stock to fit around the rubber section and hold it so the rear nut can be removed.

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Re: Some questions [message #10356 is a reply to message #10355]

Tue, 27 January 2009 12:49

SKEETER
Messages: 9
Registered: January 2009

Junior Member

Thanks again. I am sure glad I found this site, this info is invaluable.

Are there other things other than Deoxit on switches and pots that I might consider while I am in there?
I don't think I need to replace any caps, the amp sounds like it should and is not a bit noisey.
Also, is there an input resistor on this amp, like on Fenders, and if so is there a mod to change the input resistor to a smaller one?

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Re: Some questions [message #10357 is a reply to message #10326]

Tue, 27 January 2009 13:08

stevem
Messages: 4775
Registered: June 2004
Location: NY

Senior Member

yes they have a input resistor, but I would leave it in, as in some cases even with the resistor the amp will pick up local radio stations, and since so little current is flowing from the guitars pickups you have no loss of highs like some folks have stated from removing those resistors.
You will find more of a change in highs and tone from a bad or good quility guitar core.
low cap is the key, not resistance!
In fact there is a factory mod of adding a cap to ground off the input jacks to tame this.
I have even used radio shack control cleaner and lube in the pots and switches and all was fine.

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Re: Some questions [message #10358 is a reply to message #10357]

Tue, 27 January 2009 13:34

SKEETER
Messages: 9
Registered: January 2009

Junior Member

I don't mess with tuner cleaner from rat shack, I use the real magoo. I also have the best guitars made, they are all Japanese, Korean and Indonesian, so there is no problem there. Tone monsters.
On older Fender amps the reason for changing the input resistor was to make more of the signal to to the amp instead of bleeding off ( and I stated it wrong, I meant to a higher value resistor so that more signal goes to the amp).
In old Fenders that gave a hotter signal to the preamp to give the amp more punch and more of a high gain sound.

But, that isn't that big of a deal. The amp already amazes me with how much sustain it has so I don't really need the extra gain at the input.
I just thought perhaps others had done the mod and had some benefit from it.

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Re: Some questions [message #10359 is a reply to message #10326]

Tue, 27 January 2009 14:43

stevem
Messages: 4775
Registered: June 2004
Location: NY

Senior Member

If your amp was made before 11/5 71 there is a factory mod for getting more gain out of the 5066 preamp board I can turn you onto.
On a Blackface or silver face Fender with tremolo ( other than a champ or vibro champ model) if you lift the yellow wire ( right most ungrounded) from the intensity control you will get a ton more tone and recover the lost gain that the tremolo circuit sucks out.
you can re-run this wire thru a switch for when you want the tremolo to function.
What I do on the master volume silverface models is to disconnect the master volume/ boost since it sucks anyway and use that switch to open and close that tremolo circiut.
If you have a fender you will love how fat the tone will be from doing this!

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Re: Some questions [message #10360 is a reply to message #10359]

Tue, 27 January 2009 16:28

SKEETER
Messages: 9
Registered: January 2009

Junior Member

An earlier response to my original post says my Kustom was made in May of 72. If there are any mods for it I would like to know them.

I don't care for Fender that much. Some of their tube amps are good and they project well, but for stage stuff I am more of a Crate kind of guy. I have had the best luck with them for dependability and getting my sound.
If I ever run across an old Fender tube amp that is a 1x12 combo and I have the cash I would probably snag it. So thanks for the info on the mod, it is good to know.

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