MARSHALL JCM 900 - part 1 - LET'S REPAIR! EPISODE 44

Today the Tone Priest puts on his big boy amp tech pants and tries to service a 1997 Marshall JCM 900 model 4100 5881 vacuum tube amplifier that is blowing fuses. Can he get to the bottom of this problem or will he just make matters worse for this iconic amp?

Schematics:

- https://www.drtube.com/schematics/marshall/4100-60-02-2-iss11.gif
- https://www.drtube.com/marshall-jcm900/

= = = = = = =

People we like (no affiliation, just channels we enjoy and learn a lot from):

The Squishy Guitar Project: https://www.youtube.com/channel/UCdOIsOWKupFbet1zQ8zr5Rg
Uncle Doug: https://www.youtube.com/user/Stratosaurus1
Brad the Guitologist: https://theguitologist.locals.com/ and https://www.youtube.com/user/electrictoothsyndrom
Rob Robinette: https://robrobinette.com/Amp_Stuff.htm
Mr. Carlson's Lab: https://www.youtube.com/c/MrCarlsonsLab/videos
Blueglow Electronics: https://www.youtube.com/c/BlueglowElectronics/videos
Johan Sageborn: https://www.youtube.com/user/JohanSegeborn
Matthew Scott: https://www.youtube.com/c/MatthewScottmusic/videos
Dave's World of Fun Stuff: https://www.youtube.com/channel/UCOXNPo7CtnzzZ9A4GyQ6Tog
REXYLAB: https://www.youtube.com/c/REXYLAB/videos
SCAR-MY-GUITAR: https://www.youtube.com/user/scarmyguitar
ElectroBOOM: https://www.youtube.com/user/msadaghd
Jim Lill: https://www.youtube.com/user/JimLill45/videos
How old are you? https://www.youtube.com/watch?v=0QfufrqH8gA

- - - - - - -

Want to help the channel out? Below are some Amazon links to stuff I use. If you make a purchase using the links below I make a small commission:

- Hakko FX-888d soldering iron: https://amzn.to/3vR5OS1
- Multimeter: https://amzn.to/3kFo4v2
- Preamp Bible: https://amzn.to/3Y61Ukg
- Power amp Bible: https://amzn.to/40blbSV
- Hi-Fi Bible: https://amzn.to/3RiacTY
- Solder: https://amzn.to/3GeoT5h
- Switchcraft 1/4" jacks (non shorting): https://amzn.to/3X2EaN5
- F/X pedal enclosures: https://amzn.to/3WWE0Ha

= = = = = = =

This and all Tone Priest videos are for edu-tainment purposes only. Vacuum tube amplifiers can have lethal voltages in excess of 700 volts. Capacitors can retain a deadly charge even when an amplifier is turned off and unplugged. Videos are not instructional nor do they advocate anyone doing any kind of repairs on their gear. Nobody should do electrical work on anything for any reason ever. Keep your hands and belongings inside the car at all times.

tonepriest@gmail.com