Lambda Power Supplies

[MikeKE0ZUinkcmo]

I didn't want to hijack Mike's thread about his receiver's power supply, but, Lambda made a lot of different regulated tube power supply models in their hay day.   They seemed to be used by just about everybody, and they just ran and ran.   I used a few of them for several years in the early 60s.

Lambda made one supply that is a real classic and a real asset on you tube test bench.   Its their model 71,  and if you ever happen to see one you would do well to grab it.   It provides B+, Bias, and Filament power, a really handy supply.   I've had mine for quite a few years and it still sees fairly regular use.   One word of caution however, its about a 50 pound paper weight so make sure you've had your Wheaties if you're going to carry it far.

[KA2DZT]

Mike,

Yours doesn't look that heavy.  The Lambdas I have and had were all rack mounted models.  Way too heavy for what they do.  I reduced most all of them to parts. Still have some low voltage ones.  I do have a rack mounted HP regulated supply that I use.  It has zero to 500 volts, filament and bias.  I also have a regulated zero to 1500 volt regulated supply, two 10.5 inch rack chassis.  I also had a zero to 1000 volt 500ma regulated supply with filament.  It was over 100 lbs. in one 10.5 inch rack.  It had 8 6550 regulators in it.  It was reduced to parts, the 6550s were needed for other more important projects.

Fred

[Opcom]

I like the big heavy tube ones. As long as there is rack space. Rows of 6L6's 6550's, 807's, 6CD6's, etc. Life is good.

[K3ZS]

I got a Model 71 for $10 at a ham estate sale.   I used it to test a VF-1 before building a dedicated power supply for it.  It uses a slew of 6V6's as the series regulator.

[N8ETQ]

Hi,
 

   Yeah, that Model 71 is sweet... My old Model 33 keeps on running.
Prolly had it for 30 years. He uses a bunch of 6L6's as the pass elements
and also provides fil.  No bias though.

/Dan

[KC2TAU]

Is there a list somewhere of the various models of this type that Lambda made? I'd like to find one or two more to power a few military radios that I have but, not knowing most of the model numbers, I'm unsure where to start looking.

[N8ETQ]

Is there a list somewhere of the various models of this type that Lambda made? I'd like to find one or two more to power a few military radios that I have but, not knowing most of the model numbers, I'm unsure where to start looking.

Yo'

   I had a large 28V Lamda that (With Help) was used
on my GRC-19. It was 6" by 8" HxW looking at the front
but extended about 18" deep.  I recall getting a "Huge"
electric bill a couple of times when using it. Don't
recall the model number.

73

/Dan

[KB3DKS]

There is a Fluke 407? 409? that is similar to the Lambda 71 and uses 807s as pass tubes. Also an easy to find, overlooked Eico 1030 is good for receivers at up to 425v 120ma with 2 filament outputs and bias. A pair of 6L6s for pass. Can be modded to 475 at 200ma with a tube change and re-cal.
 I have a Kepco rack mount with a pile of 6L6 pass tubes and solid state control good for 550v at 500ma. Trouble with all these multi pass tube units is the high AC line draw. OK if you can afford the electric bill and heat output.

[Opcom]

Is there a list somewhere of the various models of this type that Lambda made? I'd like to find one or two more to power a few military radios that I have but, not knowing most of the model numbers, I'm unsure where to start looking.

Yo'

   I had a large 28V Lamda that (With Help) was used
on my GRC-19. It was 6" by 8" HxW looking at the front
but extended about 18" deep.  I recall getting a "Huge"
electric bill a couple of times when using it. Don't
recall the model number.

73

/Dan

Lambda seems to like running about 2x the voltage before the regulator in the fixed voltage solid state units. Wasted half the power but what comes out is clean.