external PSU connection
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The 'kubota' hv regulator looks interesting. I have ordered one to try out. Do you know if it is short circuit proof?
Cheers
Ian
Cheers
Ian
No, not short circuit proof - it's a pretty simple affair, just a mosfet series pass element, adjustable reference and a discrete differential error amp.
The ebay link I provided has an attached 'somewhat useful' schematic
Fortunately the pcb silk screen is accurate and the pcb works as it should, first time powered up.
Which is more than I can say for some other simple hv regulator pcbs I have used!
Note that there are other variants of the 'kubota regulator' out there - I like this one for it's simplicity, sensible and spaced layout.
And the cheapness I think it cost about 20usd all up assembled, excluding the external JJ can 50uF+50uF dual-cap I used
The ebay link I provided has an attached 'somewhat useful' schematic
Fortunately the pcb silk screen is accurate and the pcb works as it should, first time powered up. Which is more than I can say for some other simple hv regulator pcbs I have used!
Note that there are other variants of the 'kubota regulator' out there - I like this one for it's simplicity, sensible and spaced layout.
And the cheapness
I think it cost about 20usd all up assembled, excluding the external JJ can 50uF+50uF dual-cap I used My preference is to have just dc conductors in an external psu cable - so imho one should have psu traffo, rectification and main filtering components together.
I suppose you could have just the psu traffo on an external box, and that would give seperation from sensitive components - always a good thing.
But I would say including power rectification and/or main filtering at the remote end is going to leave you open to a very noisy cable environment - at least in a tube context, where the ac signals would be pretty large amplitudes.
Plus rectifier spraying switching transients at high voltages can't be a good thing to have locally. Defeats the purpose of seperation really.
Local filtering and regulation is OK tho
I suppose you could have just the psu traffo on an external box, and that would give seperation from sensitive components - always a good thing.
But I would say including power rectification and/or main filtering at the remote end is going to leave you open to a very noisy cable environment - at least in a tube context, where the ac signals would be pretty large amplitudes.
Plus rectifier spraying switching transients at high voltages can't be a good thing to have locally. Defeats the purpose of seperation really.
Local filtering and regulation is OK tho
Hey are these the connectors you're using?
https://www.ebay.com/itm/131856798273
Seems there are a few different sizes...
I've been looking for a solution to this - the Switchcraft Slim Line connectors are really nice for this stuff a but they are much more expensive...
Can you change the sex of the connectors? I can't seem to find a male cable mount/female panel mount.
Thanks!
Timothy
https://www.ebay.com/itm/131856798273
Seems there are a few different sizes...
I've been looking for a solution to this - the Switchcraft Slim Line connectors are really nice for this stuff a but they are much more expensive...
Can you change the sex of the connectors? I can't seem to find a male cable mount/female panel mount.
Thanks!
Timothy
'That's no a connector - *this* is a connector
http://www.ebay.com/itm/GX30-7-30mm-Dia-7Pin-Male-Eletrical-Deck-Cable-Connector-Aviation-Plug-/321293278012?hash=item4ace925b3c:g:KMEAAOSwSlBYuM94
30mm diameter ... fixed sexing only .. the price of being .. basic They do get 'cheaper' in groups ;D ;D
For higher currents (meaning I want more pin-pin seperation and insulation please!), fewer pins in same diameter.
http://www.ebay.com/itm/GX30-5-30mm-Dia-5Pin-Male-Eletrical-Deck-Cable-Connector-Aviation-Plug/322196887303?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D41451%26meid%3D79e6ca9b34d0442a8bd219128374e15e%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D321293278012
And for stupid high current, 4 pin same diameter too
..
To get properly spec'd connectors for this kind of thing, with both orientations available for panel and line varieties .. is the province of professional connector manufacturers.
It's all avail, but just not at a solution cost of 15usd per cable connect.
..
ps - for more info, see Holger's Tube Desk external psu connectors That's proper engineering
..
For the cheaper builds among us, these are .. ok.
You can address the 'safety issues' by making the psu end 'captive' (super-glue!) or by having plastic 'captive caps' and suitable warning messages.
....
If I was making commercial like, I'd be looking at something in the range of a 100 usd cable-connect solution, remembering that each cable takes 4 connectors and some suitable cable stock. .. and delivery all the way down here!
Which is a lot! Quality costs, especially in the world of rugged, multipin connectors.
http://www.ebay.com/itm/GX30-7-30mm-Dia-7Pin-Male-Eletrical-Deck-Cable-Connector-Aviation-Plug-/321293278012?hash=item4ace925b3c:g:KMEAAOSwSlBYuM94
30mm diameter ... fixed sexing only .. the price of being .. basic
They do get 'cheaper' in groups ;D ;DFor higher currents (meaning I want more pin-pin seperation and insulation please!), fewer pins in same diameter.
http://www.ebay.com/itm/GX30-5-30mm-Dia-5Pin-Male-Eletrical-Deck-Cable-Connector-Aviation-Plug/322196887303?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D41451%26meid%3D79e6ca9b34d0442a8bd219128374e15e%26pid%3D100005%26rk%3D3%26rkt%3D6%26sd%3D321293278012
And for stupid high current, 4 pin same diameter too
..
To get properly spec'd connectors for this kind of thing, with both orientations available for panel and line varieties .. is the province of professional connector manufacturers.
It's all avail, but just not at a solution cost of 15usd per cable connect.
..
ps - for more info, see Holger's Tube Desk external psu connectors
That's proper engineering..
For the cheaper builds among us, these are .. ok.
You can address the 'safety issues' by making the psu end 'captive' (super-glue!) or by having plastic 'captive caps' and suitable warning messages.
....
If I was making commercial like, I'd be looking at something in the range of a 100 usd cable-connect solution, remembering that each cable takes 4 connectors and some suitable cable stock. .. and delivery all the way down here!
Which is a lot! Quality costs, especially in the world of rugged, multipin connectors.
The psu unit #2 of this series is pretty cool ...
It has a big Edcor psu on the 'A' side, top of chassis. Awesome unit - mucho HV current, and a decent bunch of heaters too.
The 'B' side is a 60VA toroid mounted inside. This is just a heater traffo; it takes HV from the 'A' side.
I have the usual JJ dual can caps topside, and the dc heater filter caps up there too.
NOW because this unit does up to 340mA of HV and because it is solid-state fred rectifying, it's a good idea to have independent 'Power' and 'Warm Up' switches per side as well as comprehensive fuses per side and overall !
So one can power up each side 'signal units' heater first, then HV once warmed. The price of lacking a tube rectifier or 'slow start' module
IT is a solid state rectified PSU unit with 2x Kubota HV regulated rails of low-ish current (100mA total) and a -ve bias winding too .. for my 'overkill' tube limiter/eq ... and an unregulated high current (250mA) HV supply .. for a tube monitor amp.
I think it's around 100VA of heaters in use all up; a mix of 6Vdc and 12Vdc
One psu cable for the limiter/eq and another for the monitor amp off cheap 1ru chassis for 4ru total height.
Each of the signal units is in stereo
< pic to add>
It has a big Edcor psu on the 'A' side, top of chassis. Awesome unit - mucho HV current, and a decent bunch of heaters too.
The 'B' side is a 60VA toroid mounted inside. This is just a heater traffo; it takes HV from the 'A' side.
I have the usual JJ dual can caps topside, and the dc heater filter caps up there too.
NOW because this unit does up to 340mA of HV and because it is solid-state fred rectifying, it's a good idea to have independent 'Power' and 'Warm Up' switches per side as well as comprehensive fuses per side and overall !
So one can power up each side 'signal units' heater first, then HV once warmed. The price of lacking a tube rectifier or 'slow start' module
IT is a solid state rectified PSU unit with 2x Kubota HV regulated rails of low-ish current (100mA total) and a -ve bias winding too .. for my 'overkill' tube limiter/eq ... and an unregulated high current (250mA) HV supply .. for a tube monitor amp.
I think it's around 100VA of heaters in use all up; a mix of 6Vdc and 12Vdc
One psu cable for the limiter/eq and another for the monitor amp off cheap 1ru chassis for 4ru total height.
Each of the signal units is in stereo
< pic to add>
Do you have a link to the 7 pin connectors? I looked on eBay to no avail.
alexc said:For my external tube PSUs I used aviation mic/headset type connectors. Cheap and cheerful but quite rugged. They have screw locking rings. You can see them on ebay
They come in 2 sizes for 7 pin : I use the larger ones for high voltage. The smaller ones are OK for low voltage, low current apps.
They are cheap and you can also get an extra heavy duty version in 4-pin (I use for high current discrete class A amps).
The 4pin has goodly wide spaced pins and can carry some decent current. It's quite large but still fits nicely on a 1-ru rear panel.
The 7pin version is somewhat less spaced but still easy to insulate the solder pins with heatshrink for safety.
I wouldn't use xlr type connectors with small pin spacings for psu cabling (except for tube mics!) - these are quite a bit larger than the xlr multi pin types and much more suitable imho.
As usual, for the cheaper types, you can only get male chassis-mount types, and female line types, so there is the safety issue regarding the possibility of powering up the psu without the cable connected ie. PSU end male chassis-mount pins exposed and live.
You can get them with a 'safety cap' hanging off the chassis-mount connector or one can make the cable captive (fixed and not removable) at the PSU end.
My stuff is not made-for-sale so it's not an issue for me.
kambo said:
yeah that is nice - I wonder what the 4 flat contacts are.
I ordered some of those chinese specials - thanks for that - but its worth noting - the Switchcraft Slimline are high quality, reversible sex, with shield connections on the chassis of the jack so you don't have to use up a pin for shielding. Screw lock, small footprint - good for 5A per pin... More money, but more "pro" maybe
http://www.switchcraft.com/productsummary.aspx?Parent=598
I use the Amphenol/Bendix circular connectors for my mixers - these are amazing - peerless, but expensive...
Yes - that one I linked is the 7pin 30mm - it's about right sized for that many pins, in a moderate power tube context.
FOr higher power, prolly need to go to the 5 pin 30mm,
For ultimate power, 4pin 30mm.
...
I like the 7 pin because it gives a comprehensive capability!
For a step up, I would be looking at amphenol rugged multi pin - but I think that would require more space than 1RU - good in a 2ru context, especially for the higher power tube context.
The china cheapies let you try the waters before going all the way
FOr higher power, prolly need to go to the 5 pin 30mm,
For ultimate power, 4pin 30mm.
...
I like the 7 pin because it gives a comprehensive capability!
For a step up, I would be looking at amphenol rugged multi pin - but I think that would require more space than 1RU - good in a 2ru context, especially for the higher power tube context.
The china cheapies let you try the waters before going all the way
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