That's true, altough I don't like SMPS that much.....some SMPS can have problems when the filament is cold and draws a little bit more on startup.
A normal transformer doesn't mind.
That 400w power output rating a few posts back is in class C using one tube I think.
So Pushpull class AB2 for audio will be more then enough...
I’ve used these:
Millen High Voltage Connector Set Flange & Sleeve Red 37001-C/D NEW!
No affiliation.
Millen High Voltage Connector Set Flange & Sleeve Red 37001-C/D NEW!
No affiliation.
Not a fan of those things- I know a few people who have been bit by them. I'm sure they're usually fine, I'm just a bit uncomfortable with using them.
Used them a lot with zero issues. My Henry uses them.
They hold 4KV for years.
The trick to not getting bit is to make sure the hv is bled before un-coupling.
They hold 4KV for years.
The trick to not getting bit is to make sure the hv is bled before un-coupling.
I have quite a few of red and black, still in the Millen bags, but I have not used any of them yet. I have bought stuff from that seller, and it has always been first rate. I am pretty sure I got my Ameritron AL-811 from him a couple of decades ago.
I think they were the de facto HV connector back in the day if the amp and power supply were on separate chassis. Collins used them on the KWS-1, IIRC, and I think everybody else followed.
572B's don't run at extreme voltages ( by RF standards ) - only 500 or 600 more than an 811A.
edit: even the little 30L-1 sits at 2 kV unloaded. It's possible I put 572B's in this thing when I rebuilt it, they were cheap back then, don't recall at the moment.
double edit: it's got the same white ceramic base Svetlana ( Ryazan ) 811A that are in my Ameritron; this is the first time it's seen power in at least a decade, and now my entire office is filled with that wonderful hot, dusty, tube smell ...
I think they were the de facto HV connector back in the day if the amp and power supply were on separate chassis. Collins used them on the KWS-1, IIRC, and I think everybody else followed.
572B's don't run at extreme voltages ( by RF standards ) - only 500 or 600 more than an 811A.
edit: even the little 30L-1 sits at 2 kV unloaded. It's possible I put 572B's in this thing when I rebuilt it, they were cheap back then, don't recall at the moment.
double edit: it's got the same white ceramic base Svetlana ( Ryazan ) 811A that are in my Ameritron; this is the first time it's seen power in at least a decade, and now my entire office is filled with that wonderful hot, dusty, tube smell ...
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Very nice Collins. I have a Yaesu 2100B that uses a couple of 572B's.
As for the Millen connectors, my Henry amp used actual spark plug wire for the hv.
I recapped it and put a Peter Dahl transformer in it.
One very important thing with these power supplies is to NOT skimp on the cap equalizer resistors! I have an amp I built and unknowingly used substandard resistors.
If one goes it puts the HV on one cap and it blows 😱
As for the Millen connectors, my Henry amp used actual spark plug wire for the hv.
I recapped it and put a Peter Dahl transformer in it.
One very important thing with these power supplies is to NOT skimp on the cap equalizer resistors! I have an amp I built and unknowingly used substandard resistors.
If one goes it puts the HV on one cap and it blows 😱
Use a UK plug and socket.
In Wisconsin, WV, or Arkansas they probably can't be confused for 230V wall connectors.
The hot parts are recessed and shuttered.
The ones I have handled look safe for KV.
In Wisconsin, WV, or Arkansas they probably can't be confused for 230V wall connectors.
The hot parts are recessed and shuttered.
The ones I have handled look safe for KV.
Here's why I am a big fan of the modified UHF connectors (I've heard them called "deepwell" HV connectors, but I'm not sure that's the right term):
The high voltage connection is made about six inches away from the locking mechanism, which means that the HV connection is about six inches from your hands. There's a reason that Glassman uses them for their 30kV power supplies. The other nice thing is that you can use a single cable (and connector) for HV and ground. If the dielectric breaks down, it arcs to the shield (ground) rather than to a person. It is not foolproof, but I feel that it is a safer way to do it.
This is just my $0.02 on this.
The high voltage connection is made about six inches away from the locking mechanism, which means that the HV connection is about six inches from your hands. There's a reason that Glassman uses them for their 30kV power supplies. The other nice thing is that you can use a single cable (and connector) for HV and ground. If the dielectric breaks down, it arcs to the shield (ground) rather than to a person. It is not foolproof, but I feel that it is a safer way to do it.
This is just my $0.02 on this.
Good find. I see mouser has them but they ain’t cheap.
There are knock offs on an auction site.
Not sure if they’re trustworthy.
Guessing the the expensive ones are made in the same “area”
There are knock offs on an auction site.
Not sure if they’re trustworthy.
Guessing the the expensive ones are made in the same “area”
That is an absolutely beautiful 30L-1. It's hard to beat that old Collins tube gear.
Ok so did some more thinking.
I'm gonna try to get the power supply into the same chassis as the amplifier.
While a seperate power supply could be great, just for safety I think it's better to get everything in one chassis so the HV section can never be exposed in normal operation.
As tubes go the GU-81 is preferred I think.
It's less expensive and probably more durable.
Also a first estimate for the primary load gave me around 8k so easier on the OPT. looks like 6k might even be possible, altough it's stretching things.
Easier to drive.
What do you guys think about the 8k load at a voltage around 1.8kv and g2 at 600v
I'm gonna try to get the power supply into the same chassis as the amplifier.
While a seperate power supply could be great, just for safety I think it's better to get everything in one chassis so the HV section can never be exposed in normal operation.
As tubes go the GU-81 is preferred I think.
It's less expensive and probably more durable.
Also a first estimate for the primary load gave me around 8k so easier on the OPT. looks like 6k might even be possible, altough it's stretching things.
Easier to drive.
What do you guys think about the 8k load at a voltage around 1.8kv and g2 at 600v