I was wondering if it would be possible to catagorize the Dumble schematics and layouts into stickies for the various model amps, like in the Trainwreck files section.
Whoever did that in the wreck page is to be commended!
Sometimes it's very confusing to sort through the various versions and nomaclature concerning the different circuits.
Because in the threads people will refer to the HRM, Bluesmaster, #124, etc. then you have to figure out which schemo to look at.
Sorry if this is a lame suggestion.
If I had the capability I would volunteer to do it but I don't.
I was looking at the #124 schematic labeled 'version 2.7 5/12/08' and comparing it to the version by odourboy 'rev.1.7 03/06/08'. I saw a difference in the PAB relays, one shows 'NO' not connected and the other show 'NC' not connected, which is correct? I was also comparing it to the 50w layout on 'SchematicHeaven' and there are relay errors. The relay pin numbers don't seem to go with the layout or schematic.
Also the V1A and V1B pin numbers are reversed, also the PI V3A and V3B are reversed as well. On V1a pin 2 goes to the Normal jack not pin 7. On v3a pin 2 goes to the .05 uf cap not pin 7.
Dave
Instructions...I don't need no stinkin instructions
The tube pin number difference is because of orientation, it is theorectically quieter to cascade the tube using the pin 7 grid stage feeding the pin 2 grid stage, and you see some of the "real" McCoy's wired that way.
Relay confusion - NC is generally accepted to be "not connected" or "no connection" except when you are referring to switches or relays then it means "Normally Closed" and the NO means "Normally Open".
EDIT - never mind, I misread the post, the correct way to wire a relay is to decide how you want it when the relay supply fails. I want the OD and PAB to be off if there was a loss of relay power.
joebob wrote:I was looking at the #124 schematic labeled 'version 2.7 5/12/08' and comparing it to the version by odourboy 'rev.1.7 03/06/08'. I saw a difference in the PAB relays, one shows 'NO' not connected and the other show 'NC' not connected, which is correct? I was also comparing it to the 50w layout on 'SchematicHeaven' and there are relay errors. The relay pin numbers don't seem to go with the layout or schematic.
Also the V1A and V1B pin numbers are reversed, also the PI V3A and V3B are reversed as well. On V1a pin 2 goes to the Normal jack not pin 7. On v3a pin 2 goes to the .05 uf cap not pin 7.
The relays in that schematic are supposed produce PAB and OD when the coils are energized (and thus work with any standard-wired Dumble foot pedal). The part number for the relay is given in the schematic, but the part is no longer produced.
The tube socket wiring in that schematic correctly represents the tube-socket orientation that is shown in the pictures of #124.
Realize that each Dumble is different They are not all like #124!
They are not all like #124!