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kustom 100 [message #15331]

Mon, 28 February 2011 19:58

sipk
Messages: 7
Registered: February 2011
Location: uk

Junior Member

I hope you can help me, i have a Kustom 100 in blue tuck and roll,with a 2x12 cab, i am trying to date it, i have found quite a few pictures on line, but as yet no reference to its exact age,can you date them with the serial numbers is there a listing somewhere ?
Some time ago i put a transformer to convert it to uk voltage and this works fine apart from the effect channel gets a nasty earth buzz, i would like to eliminate this, so a wiring diagram would be useful, has anyone else converted one of these to 240V ? it sounds great on the clean channel, and is ok until you crank it and dip the foot switch, but it would be nice to get it back to where it should be without carrying an external transformer, thanks in advance. Simon

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Re: kustom 100 [message #15332 is a reply to message #15331]

Mon, 28 February 2011 20:27

pleat
Messages: 1452
Registered: June 2004
Location: Belding, Mi

Senior Member

Greeting from the USA. Your amp if it is a amp and speaker cabinet in one housing would be a K100-7 with 2 12" speakers. It sounds like your effects channel may have a issue if the right normal channel is working fine. Dating the amp can be figured if you have a serial number you can post.
Pleat

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Re: kustom 100 reply [message #15336 is a reply to message #15332]

Tue, 01 March 2011 06:49

sipk
Messages: 7
Registered: February 2011
Location: uk

Junior Member

Hello USA,and thank you Don for such a fast reply. Here are all the numbers on the back of the head,
K100-2
47448
PATENT NO 210.129
The cab does not seem to have an I D plate, it appears to be two 12 inch celestions on top of each other. THANKS again for helping me out, it is much appreciated. Simon Razz

[Updated on: Tue, 01 March 2011 06:50]

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Re: kustom 100 reply [message #15340 is a reply to message #15336]

Tue, 01 March 2011 13:49

pleat
Messages: 1452
Registered: June 2004
Location: Belding, Mi

Senior Member

So you have the piggy back K100-2 head and seperate speaker cabinet. The serial # dates it to Oct. - Dec. 1969
What I missed is when you said (it sounds great on the clean channel, and is ok until you crank it and dip the foot switch) The amp you have is a single channel with effects. Does the amp sound good until you step on a footswitch to activate or de-activate the effects, or are you talking about a stomp box effect? Puzzled about the footswitch you mentioned.
pleat

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Re: kustom 100 reply [message #15341 is a reply to message #15336]

Tue, 01 March 2011 14:08

C4ster
Messages: 686
Registered: June 2001
Location: Mukwonago, WI (Milwaukee...

Senior Member

Simon,
Since you are in the UK, I would presume your power is 220/380. I would suggest that you replace the power transformer with a 220 volt primary and a 48volt center tapped transformer(24volts each side). The transformer should be rated at least 60VA. From your first post, I am confused. Did you mount the step-down transformer inside the case or is it sitting outside? If you mounted it inside the case, most isolation/step-down transformers are not shielded which will create a ton of magnetic interference that will drive right into the circuitry and buzz like hell. You need to keep a transformer like that away from the electronics or shield it. Here is a Triad Magnetics transformer that might work for you. It is a 115/230 volt primary and a 24/48 volt secondary. The model is VPT48-2080 and costs USD $39.62 It has an easy 1 screw mount. I hope this helps in some way.
Conrad

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Re: kustom 100 reply [message #15352 is a reply to message #15340]

Fri, 04 March 2011 13:42

sipk
Messages: 7
Registered: February 2011
Location: uk

Junior Member

Ok thanks for dating it, that is nice to know, i think Conrad has hit the nail on the head , as i mounted a step down tranformer directly behind the effects panel,so the buzz is probably,just a result of that... i tried unplugging the reverb well, and everything was better,so i think that it is picking up the rransformer, i shall try to shield it better when i figure out what sheilding is !!! thanks for your help, Simon Razz

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Re: kustom 100 reply [message #15354 is a reply to message #15352]

Fri, 04 March 2011 15:25

C4ster
Messages: 686
Registered: June 2001
Location: Mukwonago, WI (Milwaukee...

Senior Member

Hi Simon,
Transformer shielding is a very involved procedure completed to the transformer during the winding process. It would be great to wrap some aluminum foil around the transformer and, presto, no more hum. But the magnetic field will get through. The best answer is distance. Make a small box for the transformer with the proper mains cord and an outlet for the amp. Set it on the floor behind the amp and your hum is gone. I guess it's no worse than an effects board. And it will remove some weight from the amp head.
Conrad

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Re: kustom 100 reply [message #15355 is a reply to message #15354]

Fri, 04 March 2011 17:49

sipk
Messages: 7
Registered: February 2011
Location: uk

Junior Member

Thanks Conrad, i moved the reverb well away from the transformer, and that has eliminated a lot of the buzz, and now the reverb can be used, just not at full wack. i shall look at getting the VPT48-2080 at some point,Quick question here... would that be to replace the two transformers that are now in the amp? Or just a better shielded version of what i have now...Sorry if thats a daft question, but if i know the output from the original transformer, and the input voltage is 240 v then, can i not find a transformer with those specs?

Again i apologise if thats what you meant first time around Rolling Eyes

Simon.

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Re: kustom 100 reply [message #15357 is a reply to message #15355]

Fri, 04 March 2011 23:01

C4ster
Messages: 686
Registered: June 2001
Location: Mukwonago, WI (Milwaukee...

Senior Member

Simon,
The transformer I specified for you would work as a 240 volt mains transformer. It could also be wired for 120 volts. It would replace both transformers. It is a different style case as there really is no case. The primary windings (2) would be hooked in series and there would be instructions supplied with it. The secondary would also be hooked in series with the center connection being the ground (earth). It should work as torroid transformers have better shielding. Kustom was never intended for international markets but I understand there are some 240 volt units out there. Who modified them is unknown to me.
Conrad

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Re: kustom 100 reply [message #15358 is a reply to message #15357]

Sat, 05 March 2011 09:51

sipk
Messages: 7
Registered: February 2011
Location: uk

Junior Member

Fantastic thankyou very much. S

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Re: kustom 100 [message #15361 is a reply to message #15331]

Sat, 05 March 2011 13:27

stevem
Messages: 4733
Registered: June 2004
Location: NY

Senior Member

Simon, also note that the Celestion speakers are not the original ones that the cabinet came with.
If your cabinet has its orignal speaker jack mounting plate it will say what it was loaded with at birth, these would be as follows.
KEI
CTS
Jensen
Altec, or JBL.
I would check the Impedance of your speakers as two 16 ohm drivers wired in parallel or two 4 ohm drivers wired in serise is what you need and I know that Celestion does not make many 4 ohm drivers.
The K100 amps want a 8 ohm load as standard so to speak if you and it to output its optomistic 60 watts RMS, as these really only do a bit over 50 watts even with todays more common 120 to 125 volt AC power here in the states!
If you do find that you have a 4 ohm load from you Celestions then do not play the amp at more than half volume or you WILL at some point over heat the output stage and blow it!

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