What do the users think? My three supplies in use have no problems starting with 15VAC nominal. Is anyone else seeing a reluctance to start?
Hoping to resolve this before I order the round 2 parts. Thanks for your input.
Hoping to resolve this before I order the round 2 parts. Thanks for your input.
I have build the PSU's with the components as supplied in the kit and have no startup problems at all,regardless off load or output voltage.
I do however use a fair margin in the in/output voltages (at least 6 volts).In testing i used much less of a margin and still had no problems.
kro5998
I do however use a fair margin in the in/output voltages (at least 6 volts).In testing i used much less of a margin and still had no problems.
kro5998
the input - output voltage differential is determined by the series pass transistor dissipation capability. this imho is the primary consideration.
Tony, the series pass resistor is not used in the latest design.It isn't used in my PSU's either so the limiting factor with a high voltage diferential is the dissipation off the MJE's.
kro5998
kro5998
Jens, can you let us have the Eagle .sch and .brd files, please? Or will you put them up on delta-audio.com so that some of us can pick them up?BobEllis said:Jens has the Eagle files.
kro5998 said:Tony, the series pass resistor is not used in the latest design.It isn't used in my PSU's either so the limiting factor with a high voltage diferential is the dissipation off the MJE's.
kro5998
sorry i only looked at the scheme at the earlier pages, has there been great change? anyway, i said transistor, not resistor...
I've posted the current schematic on my page. We eliminated the CRC filter, it is now just two parallel caps. (1500 uF in the kit)
Is this a recent change? I can't seem to find any differences in the schematics since I downloaded it in the beginning of June.BobEllis said:I've posted the current schematic on my page. We eliminated the CRC filter, it is now just two parallel caps. (1500 uF in the kit)
No Hans, this change was made early on - between prototype boards and the first production boards. Other than the recent discussion about possible value changes to resolve some startup issues, the basic schematic has been unchanged. Version 2.2 is current.
Tony said that he had looked on the early pages and may have seen that schematic, so I wanted to make sure that he was current.
Tony said that he had looked on the early pages and may have seen that schematic, so I wanted to make sure that he was current.
No Avi, not this time. Everything else is included, though. Add a transformer and you're ready with +/-15V.
LAST CALL!
I won't shut you out if you don't get your order in by the end of the day today. I'm going to place the board order on Monday.
I'd appreciate a heads up if you plan to order but won't be able to send a payment today. Just let me know what you want and when you think you'll be able to send payment.
I won't shut you out if you don't get your order in by the end of the day today. I'm going to place the board order on Monday.
I'd appreciate a heads up if you plan to order but won't be able to send a payment today. Just let me know what you want and when you think you'll be able to send payment.
Jens and Bob
I tried the 1k5 and it seems to work all right so far with only one opamp connected.
Will it still be all right with more opamps connected? Bob mentioned the problem was load dependent.
Dick.
I tried the 1k5 and it seems to work all right so far with only one opamp connected.
Will it still be all right with more opamps connected? Bob mentioned the problem was load dependent.
Dick.
Dick,
You will be able to start the regulator with something like 0.5A load with the 1k5 resistor i place.
\Jens
You will be able to start the regulator with something like 0.5A load with the 1k5 resistor i place.
\Jens
Jens, do you think you would like to make the Eagle .SCH and .BRD files available to us? I saw the PSU2 data on your site, but the PDF files are not of much use to make good PCBs from, because my film maker can't use his Gerber plotter to make films from PDF. He needs Gerber files. Do you think you can give us the Eagle files?
tcpip,
I'm not sharing any of my eagle files - it's just a principle of mine. Bob has the original gerbers, and runs the GB - I leave it up to him to deside whether or not to share these.
\Jens
I'm not sharing any of my eagle files - it's just a principle of mine. Bob has the original gerbers, and runs the GB - I leave it up to him to deside whether or not to share these.
\Jens
Thanks for the clarification, and sorry I bothered you about it. Since you had put up the Eagle files for one or two other projects on your Website and on this forum, I thought maybe you are open to sharing all your projects' files.JensRasmussen said:I'm not sharing any of my eagle files - it's just a principle of mine. Bob has the original gerbers, and runs the GB - I leave it up to him to deside whether or not to share these.
Thanks anyway.
Boards ordered 21 August
I have some extras coming, order as above through my website.
The boards are due to ship to me on 5 September, I should start shipping the following weekend.
I have some extras coming, order as above through my website.
The boards are due to ship to me on 5 September, I should start shipping the following weekend.
startup problem
My first constructed power supply board (from the group buy) would not start reliably with a load connected.
Output voltage is set to +/- 12.16V
Either plus or minus side would start but not both.
Both sides would start with no load.
I have connected a 1N4007 diode to each of the ground connections - both plus and minus outputs. Each output ground wire is connected to the other end of each diode.
With this setup, both plus and minus sides have started
immediately with a load of slightly over 200ma. There
have been no failures after numerous on/off cycles.
photo attached
jb74
My first constructed power supply board (from the group buy) would not start reliably with a load connected.
Output voltage is set to +/- 12.16V
Either plus or minus side would start but not both.
Both sides would start with no load.
I have connected a 1N4007 diode to each of the ground connections - both plus and minus outputs. Each output ground wire is connected to the other end of each diode.
With this setup, both plus and minus sides have started
immediately with a load of slightly over 200ma. There
have been no failures after numerous on/off cycles.
photo attached
jb74
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