I am learning how to start a thread......and what would you suggest as the correct topic for the thread???
In the mean time, if you think my questions are off topic, please send your answers to my email address king4joy@.....com
Thankyou...
Go the the tubes category and you will see new thread button to the top left. Name it ''Help kill insect like noise in my tube amp'' or something.
P.S. Don't post emails openly, they can be spam targets. If I think of something to post too it will be in your thread.
Thankyou...but on second thought...the questions are kind of related to SSHV2, because the insect like noise is noticed after using the SSHV2 board...
Change to resistor loads to compare, maybe you got oscillation on your CCS for loads, check with scope that your B+ rails are clean straight lines (ac in for scope button). Make sure its not a minor buzz from grounding or heaters arrangement that was covered by hum before and now you noticed.
Salas, I will change back to resistor loads and compare and report back....I do think that the CCS loads are main part of the problem....I am using Rod's board for my filament and he suggested to use LED instead of resistors for biasing.....I will work on all these with time and helps from you and this forum...this is part of the fun of DIY....I think...
Mind The Cap
Merlin's photo where the still unpopulated C1 pads can be clearly seen is an opportunity to remind something for when constructing. Only the two left hand pads are to accept C1's one leg, all the others to the right are to accept its other leg. They are staggered for various standard pitch capacitors that you may find. Watch the legs to always span the left black gap in the picture in other words, and keep the cap just a wee bit proud off board for its underside not to touch any free pads, its important.
@KingForJoy
That ain't any new SSHV2, its just Merlin's yet another SSHV2 build.
Merlin's photo where the still unpopulated C1 pads can be clearly seen is an opportunity to remind something for when constructing. Only the two left hand pads are to accept C1's one leg, all the others to the right are to accept its other leg. They are staggered for various standard pitch capacitors that you may find. Watch the legs to always span the left black gap in the picture in other words, and keep the cap just a wee bit proud off board for its underside not to touch any free pads, its important.
@KingForJoy
That ain't any new SSHV2, its just Merlin's yet another SSHV2 build.
Attachments
o.k., I just feel the need to get out the sledge hammer for treating my SSHV2 built
Its for my D3a phono preamp, which played nicely with the first version of the shunt. I then set up the SSHV2, clearly better...and then I accidently shorted the input, and from then I replaced 3 sets of semis and couldn't get it running again. Ruined the PCB of course during the process.
Then I asked a friend to let go of one of his spare shunt PCB, ordered new semis and populated everything completely new; worked fine yesterday from the beginning.
When trying to mount it in the encosure, I again shorted the input accidently! (by just one strand of the wire which was peeking out of the bundle)
Before I had 290V input / 240v out set at 50mA, tubes eating 25mA.
Now when I set the current to 50mA, the input voltage drops to 243V, out still at 240.
When setting current to 30mA, input gets up to 280V again, but current ist too low.
And in either way the IRF840 is getting pretty hot, so something is eating a lot of current here.
I still can adjust both trimmers, and I already replaced Q1 to no avail.
Before I order new semis AGAIN and tear everything apart and replace all semis AGAIN, does anyone has a hint where to look first?
Maybe you know the feeling when you just want to open that window and get rid of the problem the easy way
Its for my D3a phono preamp, which played nicely with the first version of the shunt. I then set up the SSHV2, clearly better...and then I accidently shorted the input, and from then I replaced 3 sets of semis and couldn't get it running again. Ruined the PCB of course during the process.
Then I asked a friend to let go of one of his spare shunt PCB, ordered new semis and populated everything completely new; worked fine yesterday from the beginning.
When trying to mount it in the encosure, I again shorted the input accidently! (by just one strand of the wire which was peeking out of the bundle)
Before I had 290V input / 240v out set at 50mA, tubes eating 25mA.
Now when I set the current to 50mA, the input voltage drops to 243V, out still at 240.
When setting current to 30mA, input gets up to 280V again, but current ist too low.
And in either way the IRF840 is getting pretty hot, so something is eating a lot of current here.
I still can adjust both trimmers, and I already replaced Q1 to no avail.
Before I order new semis AGAIN and tear everything apart and replace all semis AGAIN, does anyone has a hint where to look first?
Maybe you know the feeling when you just want to open that window and get rid of the problem the easy way