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Newbie w/ '72 Charger Part 2 [message #9385] Sun, 06 April 2008 00:02 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member Askin' for an opinion first: From the coding on the speaker (15838J), it appears to be a Peavey made by Eminence. Is it Kustom worthy? I'm in need of the power indicator jewel. All I seem to find are the round ones, mine is square. Bulbs I can find. I cleaned the pots out, but still no adjustability on anything but the volume. I'm going to take the head back out and do some ohmin' tomorrow. I have about a 1000 2n3904s and 6s that I inherited about 10 years ago. Would it be worth it to go through and "upgrade"? Does anyone have schematics for these that they could hook me up with? Michael Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9386 is a reply to message #9385] Sun, 06 April 2008 13:37   LesS Messages: 477 Registered: December 2002 Senior Member How does the Peavey speaker sound? If you like the sound, I would say that it is "good enough" for the Kustom amp. The main question is whether the speaker is designed for lead, PA, or bass. If it is a PA speaker, it will probably have good mids and highs, and you might actually like the sound (you might need to turn up the bass EQ a little.) I have used the JBL MI115-8A and MI-15 (made for PA and guitar) for bass and I liked the sound until I changed to a real bass speaker. This is in a Kustom K115SC (K100C-6) - has the exact same speaker enclosure size as your Kustom Charger. The MI-15 required an EQ adjustment of +10dB at 80 Hz to almost equal the bass response of a 2x12 with Eminence Basslites. (Bass speakers that I use in my Kustom cabinets now include Eminence Basslites, Madison Knights, and Peavey TVX.) As far as power handling, you should be OK. Most modern 15 inch speakers can handle 75 watts. I am sure you would have already noticed this, but do you have the top cover for the amplifier chassis? - originally it had the schematic on it. -Les S Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9387 is a reply to message #9386] Sun, 06 April 2008 14:39 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member Thanks for the reply LesS! re: Speaker I like the sound of it, so far. With the BMT pots having no effect, it's hard to tell where "the settings" are, as far as the pre-amp PCB goes. re: Schematics Nope, none on the lid, or taped anywhere else, for that matter. Updating my previous post, I think I found the main culpret. The mid pot has busted loose. Someone had tried to secure it with a piece of wire through the tab holes and tacked to the shaft on the front. Reading a few previous posts, on the PC5066 board, the mid is a 2K, right? I've tried to track down a 2K, but having difficulties. When I take it to work tomorrow, I'm gonna strap a 1K resistor in its place. Are there any components I should update while I have it out and my Pace Station is up to 725C? Thanks for any and all info!! Michael Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9390 is a reply to message #9385] Mon, 07 April 2008 06:19   stevem Messages: 4733 Registered: June 2004 Location: NY Senior Member Its not hard to find a 2k pot with a 3/8" thread, but it is hard to fine one made for circuit board mounting! What I have done is used a regular pot, but I run the wires to it off the bottom of the board, which means you will need about 10 inches of wire. Do not use ribbon cable as I have seen some jerk techs do, use 3 seperate runs of stranded copper wire. You will not get any better sound out of these amps other than upping the two main filters to about 8000 to 10,000 MFD each if you are using it for bass guitar for better punch, tone wise different brands of the 14 pin IC chip do sound slightly different so if you install a plug in IC socket you can try different ones. These ICs are getting hard to find, I just picked up 7 of them and with shipping and handling their darn near 20 dollars each! Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9391 is a reply to message #9390] Mon, 07 April 2008 06:45 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member Thanks, Steve! Yeah, it was the PCB mount that was stumping me. I think we have some older junk analyzers at work that have a 2K that I was going to try. If they are larger, would putting a parallel across be a no no as far as audio is concerned? Also, is it possible that this is taking out my Bass and Treb functionality? All three legs are broken loose. Gettin' to the 14 pin IC, without a schematic and my limited knowledge of audio circuitry, what is its purpose? Could this be the cause of my B and T problems? Thanks, Michael <Who has been in technical support for over 20 years and knows the TRUE value of experienced knowledge> Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9393 is a reply to message #9385] Mon, 07 April 2008 12:27   stevem Messages: 4733 Registered: June 2004 Location: NY Senior Member If you give me a fax number, then Tuesday I will fax you the schematics for that amp. With out that pot in circuit the other controls will not work much if at all. just to see if you have any other circiit troubles you can twist two 1k 1/2 watt resistors in serise so that you have three leads, and then solder that in as if it was the pot set half way up. I have been trying to find a replacement switch for these amps and the other Kustom models that use that type of switch, and every time I find one that will drop in or can be used with little modifications I find it has been discontinued by the manufacturer. This has happended no less than 3 times, but I am still looking. If you get some polystyrene plastic from a hobby shop you can cut it into a strip of the proper lenght and width, and then heat it with a hair dryer to bend it into a sharp cornered C shape and use it as a replacement push button head for the switch. Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9394 is a reply to message #9393] Mon, 07 April 2008 13:31 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member Doin' that would be muchly appreciated! Work FAX put ATTN: Michael area code 919 prefix 552 last 3991 (Broken up for webot purposes) email eltumi at earthlink dot net Same On the mid pot, 1 leg and wiper are tied together and the third leg is completes the circuit. I put a 1K 1/2 watt in its place and will try it when I get home. Thanks, Michael Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9395 is a reply to message #9385] Tue, 08 April 2008 06:08   stevem Messages: 4733 Registered: June 2004 Location: NY Senior Member I will fax you it on wenseday. Ok, so its wired in a a veriable resistor, I did not have the schematic in front of me when I posted that. Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9396 is a reply to message #9395] Tue, 08 April 2008 09:09 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member I will fax you it on wenseday. That's cool. I'm not being held up by the lack yet. Ok, so its wired in a a veriable resistor, I did not have the schematic in front of me when I posted that. Not a problem. I've encountered a circuit or 2 in my day. It was class time at work with the guts of the bad one layin' out. We've got a young guy who's goin' to Tech School, so I've been showin' off this "Museum piece". He's a musician as well, so that adds to it. I'll be doin' more potentiometer searchin' today, so I can replace all 4 at the same time. Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9398 is a reply to message #9396] Tue, 08 April 2008 11:32 chicagobill Messages: 2005 Registered: April 2003 Senior Member Antique Electronics has some NOS Kustom pots listed on their site. I don't know if they have the 2K value, but it is a starting point. Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9400 is a reply to message #9385] Tue, 08 April 2008 12:17   stevem Messages: 4733 Registered: June 2004 Location: NY Senior Member If I am not mistaken, all that listed Kustom stuff, including schematics is from the late 80s Kustom gear and newer! Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9401 is a reply to message #9400] Tue, 08 April 2008 12:24 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member I'm right in the middle of spec-ing some CTS 450 series pots. When I finish my lunch sammiches, I'm going to go do some shaft measurin'. Does anyone know if they are tapered audio or counter clockwise tapered audio? Choices are linear, 10% audio or 10% CCW audio..... Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9414 is a reply to message #9401] Tue, 15 April 2008 12:11 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member Steve, I was never able to find the right pot in a 2K flavor. Would a 2.5K be OK, or should I parallel a 10K across the fixed terminals? Michael Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9415 is a reply to message #9385] Tue, 15 April 2008 12:14   stevem Messages: 4733 Registered: June 2004 Location: NY Senior Member Sure 2.5k will be fine. Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9425 is a reply to message #9415] Wed, 16 April 2008 19:21 eltumi Messages: 26 Registered: April 2008 Location: Raleigh, NC Junior Member Steve, I don't know if you got my email the day of the FAX, but thanks for the schems..... Michael Report message to a moderator

Re: Newbie w/ '72 Charger Part 2 [message #9426 is a reply to message #9385] Thu, 17 April 2008 05:59   stevem Messages: 4733 Registered: June 2004 Location: NY Senior Member Your welcome. If you have any question let me know, as faxed ones can be hard to read sometimes. Report message to a moderator

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