JCM-800/2204 Build
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Re: JCM-800/2204 Build
LOL!!! Ah...the wonders of modern day graphics software.
Copy..paste...flip left....flop down.......done!!
Rock on,
Dave O.
Copy..paste...flip left....flop down.......done!!
Rock on,
Dave O.
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Re: JCM-800/2204 Build
Here is a scheme that I hacked up. The contraption is inserted at the junction of what is normally the 100k (here 56k) CF resistor and the corner of the slope and treble cap.
The change to a 56k CF is not needed, it's just a taste thing. Some modern tubes have problems with startup and become magma.... stay away from modern Tung-Sol.
NOTE: Put the CF resistor and the 10k split right on the pin of the socket. At least the CF R. (quieter)
The 25kl is the squash control, a variable dump to ground.
Shown for example with 3 way switch for selection. I use a 6-way switch with 5 variations of clippers:
1. null
2. red LED
3. 20v zeners
4. transistors
5. 12v zeners
6. 5.1v zeners (or 1n914 pair)
I think I have it right here.
The change to a 56k CF is not needed, it's just a taste thing. Some modern tubes have problems with startup and become magma.... stay away from modern Tung-Sol.
NOTE: Put the CF resistor and the 10k split right on the pin of the socket. At least the CF R. (quieter)
The 25kl is the squash control, a variable dump to ground.
Shown for example with 3 way switch for selection. I use a 6-way switch with 5 variations of clippers:
1. null
2. red LED
3. 20v zeners
4. transistors
5. 12v zeners
6. 5.1v zeners (or 1n914 pair)
I think I have it right here.
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Re: JCM-800/2204 Build
AWESOME Miles!
Thank you very much for sharing that!!
Dave O.
Thank you very much for sharing that!!
Dave O.
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Re: JCM-800/2204 Build
I tried draw'ring it in a grid in PSP (whole amp) but it was getting out of hand.
I never draw anything and just work from memory. Being 48 makes me think I have less than a couple years before that isn't going to work so well anymore. I need to get busy on a decent program for schematics.
What was I saying?
I never draw anything and just work from memory. Being 48 makes me think I have less than a couple years before that isn't going to work so well anymore. I need to get busy on a decent program for schematics.
What was I saying?
Last edited by Reeltarded on Fri Jul 12, 2013 5:28 pm, edited 1 time in total.
Re: JCM-800/2204 Build
What you have described in your first post in this thread is a cross between the Friedman BE100 and a Cameron CCV.....You have some small changes.... damn close though...Reeltarded wrote:Mmmm.. nope.
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Re: JCM-800/2204 Build
Damned. Dave and Mark must have gotten my notebook.
Do you have schematics for those?
Do you have schematics for those?
Re: JCM-800/2204 Build
Or you have theirs!!!Reeltarded wrote:Damned. Dave and Mark must have gotten my notebook.
Do you have schematics for those?
I do have the schematics for both those pre-amps...
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Re: JCM-800/2204 Build
Miles, there are quite a PCBExpress and JSchem files to start from here:
http://www.el34world.com/Forum/index.php?topic=581.0
Would save you quite a bit of time. Alot done by tubenit.
http://www.el34world.com/Forum/index.php?topic=581.0
Would save you quite a bit of time. Alot done by tubenit.
We'd like to see'mI do have the schematics for both those pre-amps...
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Re: JCM-800/2204 Build
Aha good deal. I recently lost my desktop to a controller crash that put me somewhere around c. 1868.
Yeeehaw, pard'ner..
Yeeehaw, pard'ner..
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Re: JCM-800/2204 Build
Use that iPhone for something good...draw a picture in the dirt with a stick and upload it to us.Aha good deal. I recently lost my desktop to a controller crash that put me somewhere around c. 1868.
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Re: JCM-800/2204 Build
Don't push a crazy man, you nut.
Re: JCM-800/2204 Build
Chris,
I would like to see those schematics if you are able to share them.
Cheers,
Dave O.
I would like to see those schematics if you are able to share them.
Cheers,
Dave O.
Re: JCM-800/2204 Build
With London Power's power scaling you could set different power controls for low and high gain modes. I don't know if it's easy to do with VVR. That makes the Hi/lo foot switch a lot more usable
Pablo
Pablo
Re: JCM-800/2204 Build
Starting to throw some parts onto a drawing to see how it will all lay out.
Regarding a multi pole clipper switch, are there any smallish 4, 5, or 6 pole options commonly used?
I have only ever done a manage a trois and the added personalities on this one are making me feel a little inadequate.
TIA
Dave O.
Regarding a multi pole clipper switch, are there any smallish 4, 5, or 6 pole options commonly used?
I have only ever done a manage a trois and the added personalities on this one are making me feel a little inadequate.
TIA
Dave O.
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Re: JCM-800/2204 Build
2 pole 6 position from AES. Like $3. I used to have different bright switches on the other side to compliment the gain changes.
Except for the cap and 10k resistor you are looking at my clipping rig. I ganked it to make room for new circuit testing. I stared at it for an hour until I was sure I felt like completing this today.
I should have waited.
Except for the cap and 10k resistor you are looking at my clipping rig. I ganked it to make room for new circuit testing. I stared at it for an hour until I was sure I felt like completing this today.
I should have waited.
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Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.