Q for ampdoc1

[loverocker]

Um... any chance you could reduce the resolution of that Express schematic you just added to the other thread? It's huge once it's open (about 8000x6000 pixels - 60+MB) and my PC slows to a crawl even when I open the thread. I saved it, but I can't resize it myself because my computer chatters away for 15 minutes before saying "No way, dude, buy me more memory..."

You'd make an old man very happy if you could resample it to say 2000x1500 pixels or so...

[oggidog]

Try this one on for size.

[loverocker]

Ta muchly

[tubedogsmith]

hey Ampdoc1, where'd you get that schematic?

[Omar]

Try this one on for size.

oggidog
Could you repost the pic? When I was cleaning up ampdoc's picture I deleted your by accident. Sorry about that!

Omar

[oggidog]

here you go

[ampdoc1]

tubedogsmith,

I reverse engineered that Kelly '90 amp when it came through my shop in the early 1990's. There are two small mistakes: the 10pf "bright" cap should probably be 100pf, and in the original amp the standby switch was between the 1st filter section and the 1000 Ohm resistor.
I've built two amps using this basic configuration (but with some modifications to reduce the output power). They both had that incredible dynamic response (head/hands/amp) and sounded great.
I'm currently building a TW/Dumble clone and just got one of the TwoRock Ruby kits in today. 'Ya just can't have too many amps like these!

David HIcks

[tubedogsmith]

Yeah, the reason I asked is because that's the first correct schematic I've ever seen posted.

[Allynmey]

Hi ampdoc! That's a great schematic. Thanks for posting it. What we need now is a full layout to follow...I guess I'll have to do it !

I'm working on a full layout from wall outlet to speakers to make things easier to understand and follow when we build our 'wreck clones. I will post it here when I am done. It's a little slow due to my brain, experience, and available time.

When I'm done I would appreciate some of the more experienced builders here to critique and correct my mistakes. Maybe we will have a good DIY layout soon for 'wreck enthusiats. I have a couple of questions for my layout. Any help would be appreciated.

1. Your version is labeled A1b. Many people here say the A1a is the closest. Since you have actual experience with a Trainwreck Express and have worked on them, what differences did you find between the builds? I see that there is a difference in the diodes in both the power section and the OT primaries.

2. What PT and OT trannys are you using? I have Mooses' set. They are dual tapped for the PT secondaries and the impedence primaries on the OT. Do you use 300V Sec. on the PT? Mooses' PT also has 260V. What impedence on the OT? Mooses' has both 5200 and 6600 ohms What do you use?

Any help would be great so I could get a usable layout together for posting.

Thanks,

Allynmey

[ampdoc1]

I have the layouts I took from the original, for the preamp, power supply and the control wiring. I will try to get them all in a presentable form over the next few days and post them on the FILES forum. This is also easier for me as I have sent these out individually to numerous people already.
I assigned that A1b number after I modified one of those available drawing pages. I don't know how accurate the A1a amp is,...it may well be perfectly accurate for a given amp. The A1b (with the exceptions of the couple of transcribing errors that I have noted) is absolutely accurate for one amp: the Kelly '90 Trainwreck Express.
Both amps I built were made using existing Fender chassis and transformers with a PCB board I designed and had made by ExpressPCB. I don't claim to have "golden ears", but IMO any improvements using specific transformers, point to point wiring, high dollar caps, carbon comp resistors, etc, would be INCREMENTAL at best. The basic amp gain stage design by KF is the key!
I have talked to Moose about the Heyboer transformers, and I'm sure they are great, as well as affordably priced. I'm planning to buy some for my next project, a "Frankenstein" design that includes the TW pre for a clean channel, driving a Dumble OD pre.

David Hicks

[Omar]

ampdoc
Let me know when you want to post the layouts in the Files section. Currently, I'm the only one that can post in that section for a couple of different reasons.

I'm still looking for a web based solution for uploading files so we can put file descriptions and categorize them. Let me know if anyone has any ideas.

Omar

[erigm]

David,

Did you measure the pots at those values or were they written on the pots?

[ampdoc1]

Erigm,

I REed the Kelly amp in about 1991 or 92, and don't remember many details from those years, except I KNOW i had more hair!
All kidding aside, I THINK the pots were unmarked and I checked them all for value and taper. But I wouldn't swear to it.
Anybody know who owns Kelly? At the time it was in my shop it was on it's way to a buyer,...might have been Billy Gibbons, or maybe the skinny was he was gonna get one! Too long ago!

David Hicks

[Allynmey]

Thanks Ampdoc, I can wait to see your layout!
Allynmey

[ampdoc1]

Omar,

I have readied a file with scans of my original take-off drawings of the Kelly '90 amp and more usuable computer generated drawings of the same. ~ 2 MB mile zipped. Tell me how to send these to you for distribution.

David Hicks