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For Sale FS: LazPro EQN (pair) - 500 or 51x compatible

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Well-known member
Nov 3, 2012
£450 per unit (inc UK shipping)
Ask me for shipping elsewhere.

I have 2. If you want both, I can offer a discount! :)

I know it's not the cheapest unit cheap, but I am just trying to cover part costs here.
Some highlights
- BC184 everywhere,
- EA-1066 transformer, Carnhill transformer,
- Grayhill switches.
- The partial kit was £150 alone, and the work to get these units working was excruciating.

THIS IS A 51X unit but can be converted to 500 by removing a jumper (see this post)

More pictures upon request :)


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Last edited:


Well-known member
Nov 3, 2012
Bumping with lowered price.
Now includes uk shipping - £625 inc shipping


Well-known member
Nov 3, 2012
I just had a bit of a chat with some people and looks like 51x has really disappeared a bit in the last few years, so very reluctantly bumping it down a bit more :(

£600 inc UK shipping


Well-known member
Nov 3, 2012
It looks like you have the TDK Lambda convertor in place. Shouldn’t this be plug and play with 500 series?
@corgan4321, you made me go do a couple of searches, and lo and behold, the old 2012 was actually very very kind!!!! :LOL:
I did populate all the VPR500 power supply parts, therefore, this unit does run interchangeably - just remove the jumper!!!!!

Finished 2 units. Ran them phase opposite and they are super tight! they begin to drift at 7kHz.
Hopefully will put them against n$$e reissues some time soon.

Pete made these too easy to build! :p

Question: my 51x is not running the 24v rail atm.
I have populated the parts for VPR 500 and am running of 16v no problems. Jumper is not in

When I finish the PSU supply, do I have to saw off the tab with the above configuration?

And - if needed in future - is taking out the TDK lambda and putting a jumper enough to go 51x 24v or do I need to remove further components?

If you saw off the 24v tab, you can ONLY run it off the 16v rails.

I haven't yet, as I don't have +-24v rails yet running on my 51x. My question is do I have to? :)
(I have populated all the VPR 16v bits)

Was hoping I could swap it in case I run out of 16v juice at home or I need to go somewhere by removing the lambda and putting the jumper in.

Removing the dc-dc converter and putting in the jumper is fine for 24v operation. The other components will be happy going nowhere.
But as soon as the 24v tab is removed, you'll only be able to run it off the 16v rails.
Leaving the tab on... without the jumper inserted is fine for 16v.

AWesome! Interchangeable between the 2 alliances! you are a genius! thanks!

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