Search found 1613 matches
- Wed May 22, 2024 3:24 pm
- Forum: Dumble Discussion
- Topic: A SSS Build
- Replies: 46
- Views: 1284
Re: A SSS Build
Sockets are how i see new.. and Belton, so means high quality.. Never failed any in my life. So there is only 0.1% of chance that sockets are a problem.. Probably output tubes..
- Wed May 22, 2024 3:22 pm
- Forum: Dumble Discussion
- Topic: A SSS Build
- Replies: 46
- Views: 1284
Re: A SSS Build
This is bad tube problem.. pls measure resistance directly on the tube pins, between 2-3.
- Wed May 22, 2024 3:16 pm
- Forum: Technical Discussion
- Topic: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
- Replies: 20
- Views: 506
Re: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
Its a shame you can't get 220uF in non polarized form in a non gigantic form factor as that would be the easiest way to deal with this problem lol. I Now i see you are too young and green.. it is ashame that you dont know this :mrgreen: : 220uF is very easy to make, from 470uF + 470uF regular elect...
- Wed May 22, 2024 3:04 pm
- Forum: Dumble Discussion
- Topic: Dumble ODS 102 Speaker Cab
- Replies: 4
- Views: 186
Re: Dumble ODS 102 Speaker Cab
Creambacks are little bit dark... Neo Creamback is maybe the best to my ears (i had all od them)
- Tue May 21, 2024 7:22 pm
- Forum: Technical Discussion
- Topic: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
- Replies: 20
- Views: 506
Re: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
Thanks for all the replies, I'll try to address everyone's points in order: -Electrostatic shield would definitely be effective in combating this issue. Unfortunately I don't know of anyone making off the shelf PT's with them included. I'm at the point now where I could fairly easily design my own ...
- Tue May 21, 2024 7:18 pm
- Forum: Technical Discussion
- Topic: OT Primary Question
- Replies: 7
- Views: 232
Re: OT Primary Question
it is ok.. also there is wide range of usable impedances for all the tubes.. nothing to worry about..in datasheets yu can find distortion vs load impedance , this is changing, also little bit he character.. but is it ok
- Tue May 21, 2024 4:53 am
- Forum: Technical Discussion
- Topic: OT Primary Question
- Replies: 7
- Views: 232
Re: OT Primary Question
PP or SE?
- Tue May 21, 2024 4:49 am
- Forum: Dumble Discussion
- Topic: A SSS Build
- Replies: 46
- Views: 1284
Re: A SSS Build
I had the same problem in one amp, when inside the box.. chassis and power transformer were extremelly hot.. while outside on the table, chassis and PT temp was just moderate, nothing to worry about... Then i discover that there is no sufficient air circulation in the cabinet, and tubes were heating...
- Tue May 21, 2024 4:44 am
- Forum: Dumble Discussion
- Topic: A SSS Build
- Replies: 46
- Views: 1284
Re: A SSS Build
I only have one fuse, 3 amp slow on input power. In Operate 118vac wall voltage 320-0-322 vac secondary. 320vac leg is also feeding bias circuit. B+ 414vdc Bias -360vdc at 5mA PT's biased to 27mA with -49 volts. if this is in operation all looks ok.. temperature is ok also little bit hot, 45 deg C ...
- Mon May 20, 2024 5:51 pm
- Forum: Dumble Discussion
- Topic: A SSS Build
- Replies: 46
- Views: 1284
Re: A SSS Build
Usually power transformer is last thing to fail..almost impossible in good wound transformer.. Also fuses should be burned before the transformer..
- Mon May 20, 2024 5:50 pm
- Forum: Dumble Discussion
- Topic: A SSS Build
- Replies: 46
- Views: 1284
Re: A SSS Build
Hmm it is strange thing.. Does PT has normal voltages in operation? Pls retest IN OPERATION all the voltages, and write here.. If they are normal, and current consumption is normal.. And transformer is hot.. then is undersized for this application..
- Mon May 20, 2024 9:31 am
- Forum: Technical Discussion
- Topic: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
- Replies: 20
- Views: 506
Re: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
otherwise, making only V1 DC supply for heaters is simple.and cheap(7812) and fixing all of the problems.. V1 matters only, sometimes V2
- Mon May 20, 2024 9:30 am
- Forum: Technical Discussion
- Topic: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
- Replies: 20
- Views: 506
Re: Common Mode Filtering - A slightly impractical approach to reducing heater induced noise
the problem in the power transforner should be overtaken by making electrostatic shield between secondary and heater winding, which need to be located at the top (last winding), and gnd this winding
- Sun May 19, 2024 9:36 am
- Forum: Trainwreck Discussion
- Topic: On Stability
- Replies: 3
- Views: 254
Re: On Stability
Lead dress is causing oscillations in higher gain... oscillations are positive feedback, and cable connected to sensitive grids is acting like an antenna.. Whatever this cable picks up, it is getting amplified. grid is multiple turn of small wire so it is real antenna.. In guitar amp there are many ...
- Thu May 16, 2024 4:59 am
- Forum: Fender Discussion
- Topic: 1976 Fender Vibrolux refresh help
- Replies: 17
- Views: 606
Re: 1976 Fender Vibrolux refresh help
for the added fuse, check what is this and why is there