Really appreciate the info. Tomorrow the new Bias pot arrives. Hope that takes care of the bias.
Updates to follow…
Thanks,
Dan
Search found 17 matches
- Mon May 06, 2024 1:33 am
- Forum: Technical Discussion
- Topic: JTM45 Build, looks alive but no sound,
- Replies: 7
- Views: 527
- Fri May 03, 2024 2:38 am
- Forum: Technical Discussion
- Topic: JTM45 Build, looks alive but no sound,
- Replies: 7
- Views: 527
JTM45 Build, looks alive but no sound,
Finished the build of a Weber 6M45P. Built Martin Manning's Deluxe Light bulb limiter and plugged it in. Light turns on, Bulb dims, looked good, Plugged the KT66 into the Bias probe, turned it on, took it off Standby and was unable to bias the amp, it starts up at 21 ma and if I move the bias pot, i...
- Sun Apr 14, 2024 10:37 pm
- Forum: Technical Discussion
- Topic: Impedence Selector Circuit Help
- Replies: 4
- Views: 453
Re: Impedence Selector Circuit Help
I caught the 100k resistor. Thanks. Ive learned so much this time around.
Dan
Dan
- Sun Apr 14, 2024 3:10 pm
- Forum: Technical Discussion
- Topic: Impedence Selector Circuit Help
- Replies: 4
- Views: 453
Re: Impedence Selector Circuit Help
Thank you so much for the response. So if I understand correctly, I should be able to to convert the impedance to 16/8/4, so long as I make sure the negative feedback remains connected to the 16 ohm OT line? It does make sense now.
Thank you!
Dan
Thank you!
Dan
- Sun Apr 14, 2024 1:07 pm
- Forum: Technical Discussion
- Topic: Impedence Selector Circuit Help
- Replies: 4
- Views: 453
Impedence Selector Circuit Help
Reached a roadblock trying to wire the impedance selector switch of the Marshall Clone I'm working on. I have a 4 pole impedance selector switch, and have identified the common with my multimeter. What I don't understand is the wire that goes from the main board to the Yellow (16ohm) wire of the OT....
- Thu Apr 04, 2024 5:41 pm
- Forum: Technical Discussion
- Topic: Testing power supply before completion
- Replies: 14
- Views: 759
Re: Testing power supply before completion
The OT is wired. I have yet to wire the main board which includes the bias, PI and the Preamp. So long as I'm not going to blow it up by plugging it in, it would be nice to see to check it out. Once the main board goes in it is extremely crowded, so much so that I have to modify the main board just ...
- Thu Apr 04, 2024 3:33 pm
- Forum: Technical Discussion
- Topic: Testing power supply before completion
- Replies: 14
- Views: 759
Re: Testing power supply before completion
This is where I'm at. I've attached the schematic showing the power section. Additionally I have the filaments wired for all the tubes and have the power tubes completely wired.
So grateful that I have such experts from this site willing to help.
So grateful that I have such experts from this site willing to help.
- Thu Apr 04, 2024 2:22 pm
- Forum: Technical Discussion
- Topic: Testing power supply before completion
- Replies: 14
- Views: 759
Testing power supply before completion
These are likely noob questions, so I apologize in advance. I’m in the middle of my 2nd build, a Marshall 45 watt plexi, and just finished the power section and really want to make sure that everything is working as it should before I continue with the build. I have checked continuity, but was wonde...
- Mon Apr 01, 2024 12:44 pm
- Forum: Technical Discussion
- Topic: Schematic interpretation, PT 125V and 120V Primaries
- Replies: 8
- Views: 354
Schematic interpretation, PT 125V and 120V Primaries
Haven't been able to find the answer online. The PT has a 125V and 120V primaries. Does the attached schematic show the 125V (BLUE) connected to the switch, or is the 120V (Brown) connected, or are both connected? If some one could explain the reasoning behind the 125V primary when the US power supp...
- Mon Mar 25, 2024 3:31 am
- Forum: Technical Discussion
- Topic: Power filter schematic change help
- Replies: 11
- Views: 627
Re: Power filter schematic change help
Can’t thank you guys enuf. The schematic is from a Weber 6M45P kit. All 10 capacitors are actually supposed to be on a vertical board attached to the lugs of the PT. Wish I knew about is beforehand. Lesson learned. It’s my second build and unfortunately I didn’t spend time with the schematic or layo...
- Sun Mar 24, 2024 2:24 pm
- Forum: Technical Discussion
- Topic: Power filter schematic change help
- Replies: 11
- Views: 627
Re: Power filter schematic change help
Then there has to be a reason for the the 2 40uf caps in series, why else would the designer opt for 2 in series over just one 20uf cap? I realize this is likely a stupid question, but I'm really trying to learn this stuff. I really appreciate you r comments as it forces me to keep studying... Thank...
- Fri Mar 22, 2024 10:04 pm
- Forum: Technical Discussion
- Topic: Power filter schematic change help
- Replies: 11
- Views: 627
Re: Power filter schematic change help
Thank you!
I think the kit used the cheapest components. Dont want to bad mouth anyone but the 10 capacitors on a vertical board seemed crazy. That was the point of the change in #s of caps.
Dan
I think the kit used the cheapest components. Dont want to bad mouth anyone but the 10 capacitors on a vertical board seemed crazy. That was the point of the change in #s of caps.
Dan
- Fri Mar 22, 2024 7:17 pm
- Forum: Technical Discussion
- Topic: Power filter schematic change help
- Replies: 11
- Views: 627
Power filter schematic change help
I bought this kit and the power filter section is a total of 10 caps on one rather small eyelet board. Kinda crazy. I want to reduce the number of caps. Can I keep the schematic as is, but assuming I use the same voltages, replace 2 40uf caps with (1) 80uf cap. and replace the each of the 40uf and 8...
- Sun Feb 18, 2024 2:39 am
- Forum: For Sale/Trade
- Topic: Amp parts for sale
- Replies: 21
- Views: 7579
Re: Amp parts for sale
Can you send or post an Inventory? I'm sourcing a 3rd gen ODS 124. Let me know whatcha got...
Dan
Dan
- Thu Feb 08, 2024 4:08 am
- Forum: Dumble Discussion
- Topic: Jumped into the rabbit hole
- Replies: 4
- Views: 312
Jumped into the rabbit hole
I started my journey to build #124. Chassis and boards were delivered today. I was lucky enough to get a set from Taylor Cox. So excellent. My question of the day has to do with power and output transformers. It seems as if Hammond and Mercury Magnetics are the 2 manufacturers that source the twin r...