Are you guys talking about R5, the current setting resistor for the zener on the FE ccs, as seen in post 663?
The CMF55 resistors you specced in the BOM are 1/2 watt rated @70ºC and 1/4 watt @125ºC.
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sole resistor needing more oomph here is LED voltage dropper
make it from two in series or parallel , whatever
make it from two in series or parallel , whatever
Re-sized to fit the UMS, so the output PCBs and Front-End will fit in a 5U. (nice!)
Many more places for wire connections. (this is a big deal...)
Silkscreen updated so all PCB follow numbering of the F5Tv3 schematic in Nelson's original article.
Many more places for wire connections. (this is a big deal...)
Silkscreen updated so all PCB follow numbering of the F5Tv3 schematic in Nelson's original article.
Lol... Sorry.
🙂 🙂 🙂
All the Aleph J boards in the store have been the "v2" - the v1 was the green prototype boards that were used as proof of concept. There were a few, very minor changes made from those to the production blue ones.
🙂 🙂 🙂
All the Aleph J boards in the store have been the "v2" - the v1 was the green prototype boards that were used as proof of concept. There were a few, very minor changes made from those to the production blue ones.
Correct Wiring - RCA Inputs to PCB
Sorry to ask this question which may be redundant - but I've been unable to see a wiring diagram that clearly shows wiring an RCA input jack to the latest rev of PCB (Blue PCB)
I understand the shield around the cable gets tied to ground at one side only, then to a STAR point; the center conductor goes to the "+IN" point.
Where does the "-IN" get connected to?
Thanks
Sorry to ask this question which may be redundant - but I've been unable to see a wiring diagram that clearly shows wiring an RCA input jack to the latest rev of PCB (Blue PCB)
I understand the shield around the cable gets tied to ground at one side only, then to a STAR point; the center conductor goes to the "+IN" point.
Where does the "-IN" get connected to?
Thanks
For single end input, ground the in- either at the board ( see the 6L6 build thread) or at the XLR plug itself.
Heh, I guess I put the iPad down while I was reading/answering the question, Jim's pictures were not up when I started the anemic answer I gave. I am mounting both RCA and balanced XLR jacks on my current build. I'm putting a switch near each pair of inputs to short the in- to ground between and to the side of the jacks. I intend to turn the switch so that when you flip the switch, it will point at the correct jack.
That's an interesting and good idea.
I'm developing a PIC/uController PCB for mine that will control power-on surge, mute signals & temperature sensing. At the minimum the temperature sensing will output a signal to drive an LED for "Thermal" or Overtemperature" and could optionally shut power at relay. It will also control any shutdown surge (i.e., discharging power caps)
Optionally, fan control - don't need to use it if you don't want but will have the control signal for variable speed according to sensed heatsink temperature. That would be for those of you that want more bias with not quite enough heatsink 😀
It will be small enough fit easily in the chassis and will not have anything in the signal path not cause any spurious noise.
Timeframe? I'd like to be done soon but I need to prototype on my bench build AlephJ before issuing any schematics (Just ordered the amp PCB's) and will put all the particulars here. I can develop in parallel in any case. If there's interest from users about getting a board, I'll have to understand how that works from DIYA or another user that's done this before about a "group buy".
I may ask some questions about the build as I go along but I see many of you (notably 6L6) have done a great job to document and provide ideas.
Gary
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Regarding circuit boards, what's normally done is you buy a small run, say 10 or 20, and sell them on group buy or similar. You have the chance to recoup the costs and make a few bucks for the next one.
OK, thanks. When the development gets to that point, perhaps I can PM you fro a discussion on how to go from there.
If anyone has anything on their wish list for this project, please post it and I'll see how it can be fit in. I think the idea for XLR selection by Bones13 is a good one. Will figure out if and how this could be done through the controller circuit. Likely a soft-switch on the front. As many don't want or plan to use XLR, it might be still nice to have the inputs and have the option one day to use it.
I am using this board for my switch circuit
The ε24 Power Switch Driver Circuit
It has capability for 2 thermistor cut offs, and can change the switch LED color with temp controlled shutdown.
I also am using a DIYAudio store soft start circuit after the relay controlled by the switch circuit.
The ε24 Power Switch Driver Circuit
It has capability for 2 thermistor cut offs, and can change the switch LED color with temp controlled shutdown.
I also am using a DIYAudio store soft start circuit after the relay controlled by the switch circuit.