I don't know how I missed this video. You have a 2205 aka 4010 five dual triodes and two pentodes. I have a 2204 DIY, three dual triodes and two pentodes with the Drake PT 1202-324/7, OT 784-139/7, and Choke 1471-263/7. I am planning some additional tube mods and rebuild of this amp. I wonder if you still have that amp and could verify for me that the PT is in fact the 1202-324/7? I need to verify that I can add two more 12ax7 tubes on the heater winding. I'll probably add two T 5A inline fuses to the heater circuit just in case. It would be a great help to me. My mods will be a tremolo circuit like the Fender Deluxe Reverb and a tube buffered FX loop. I have tried a few forums for a couple months and can't get an answer. The schematic shows two possible PTs and OTs but the confusion comes in because of some notes referring to CSA and Semko models for Canada and Sweden electric codes. Its uncanny this video shows the OT and Choke but the PT label was never quite in the frame enough to read. Anyway help...please. And thank you.
Took photos of my JCM800-2205 this morning for you, they are here - solohm.com/tmp/jcm800-2205/ . Good luck and rock on my good man, rock on! They are also on my github repo but not as easy to browse to, github.com/holla2040/valvestudio/tree/master/projects/marshall/jcm800-2205/images
@@CraigHollabaugh Dude...this is so awesome! Thank you thank you thank you. I've been tinkering around with my amp for a while, testing some voicing options and switch mods. I am doing a DIYLC file for the schematic and the physical layout. But, I have been waiting until the PT was verified before I include the tube mods and rebuild. My chassis, I had someone from ebay build 16 years ago as a 19 inch rack mount all aluminum. I kinda wish I used steel now so I could plug holes, solder to the chassis, re arrange the layout. It was my first build, I made some mistakes that I am now correcting in the rebuild. Thank you again. You are so helpful.
hi craig. my name is rudy and I own a marshall jcm 800 100 watt version of the same amp you have. could you tell me where the reverb tube is located. I asked a tech and he seems to think I need a new tube.
on my amp which is a 2205, www.thetubestore.com/lib/thetubestore/schematics/Marshall/Marshall-JCM800-Splitch-50W-2205-Schematic.pdf, the reverb driver tube is V3 and recovery tube is V4. My amp has 4 12ax7, so I'd swap some tubes and see if reverb starts working.
Very interesting! Great upload
Thanks. Stayed tuned for more guitar amp design work as well as repairs.
I don't know how I missed this video. You have a 2205 aka 4010 five dual triodes and two pentodes. I have a 2204 DIY, three dual triodes and two pentodes with the Drake PT 1202-324/7, OT 784-139/7, and Choke 1471-263/7. I am planning some additional tube mods and rebuild of this amp. I wonder if you still have that amp and could verify for me that the PT is in fact the 1202-324/7? I need to verify that I can add two more 12ax7 tubes on the heater winding. I'll probably add two T 5A inline fuses to the heater circuit just in case. It would be a great help to me. My mods will be a tremolo circuit like the Fender Deluxe Reverb and a tube buffered FX loop. I have tried a few forums for a couple months and can't get an answer. The schematic shows two possible PTs and OTs but the confusion comes in because of some notes referring to CSA and Semko models for Canada and Sweden electric codes. Its uncanny this video shows the OT and Choke but the PT label was never quite in the frame enough to read. Anyway help...please. And thank you.
Took photos of my JCM800-2205 this morning for you, they are here - solohm.com/tmp/jcm800-2205/ . Good luck and rock on my good man, rock on!
They are also on my github repo but not as easy to browse to, github.com/holla2040/valvestudio/tree/master/projects/marshall/jcm800-2205/images
@@CraigHollabaugh Dude...this is so awesome! Thank you thank you thank you. I've been tinkering around with my amp for a while, testing some voicing options and switch mods. I am doing a DIYLC file for the schematic and the physical layout. But, I have been waiting until the PT was verified before I include the tube mods and rebuild. My chassis, I had someone from ebay build 16 years ago as a 19 inch rack mount all aluminum. I kinda wish I used steel now so I could plug holes, solder to the chassis, re arrange the layout. It was my first build, I made some mistakes that I am now correcting in the rebuild. Thank you again. You are so helpful.
@@xtrchessreal You're welcome, glad it helped.
@@xtrchessreal I should have mentioned that my photos on that page are thumbnails, click to enlarge them if needed.
@@xtrchessreal Since you're working on your DIY, make sure to watch my other video on bias point choice, th-cam.com/video/3i8BYwjIxOM/w-d-xo.html.
hi craig. my name is rudy and I own a marshall jcm 800 100 watt version of the same amp you have. could you tell me where the reverb tube is located. I asked a tech and he seems to think I need a new tube.
on my amp which is a 2205, www.thetubestore.com/lib/thetubestore/schematics/Marshall/Marshall-JCM800-Splitch-50W-2205-Schematic.pdf, the reverb driver tube is V3 and recovery tube is V4. My amp has 4 12ax7, so I'd swap some tubes and see if reverb starts working.