The "Sussex" Homebrew Valve Tester.

[Mark James]

I am just starting to collect the parts together - Thanks to Keith for the manual, Martin for the PCB and Ed for the transformer. With regard to the panel meters, Giorgio does not appear to be trading on e-bay now. Can anyone recommend an alternative supplier that they have used rather than just taking "pot luck"?

Mark

[crackle]

I bought mine from http://www.ebay.co.uk/sch/yourcartma...1&_ipg=&_from=

[Mark James]

Did you find any with a 6V AC supply as I cannot see any?

Mark

[mole42uk]

Most that I have seen use either AC or DC, they have a rectifier built in so you connect whatever supply you have. It just has to be a seperate supply, not derived from the voltage you are measuring!
The ones that crackle mentioned look okay.

[David G4EBT]

Originally Posted by Mark James

With regard to the panel meters, Giorgio does not appear to be trading on e-bay now. Can anyone recommend an alternative supplier that they have used rather than just taking "pot luck"?

Mark

Giorgio trades as 'Asia Engineer' and is here:

http://stores.ebay.com/Asia-Engineer...sub=1043767018

The manual calls for three meters - 0-200V DC; 0-200mV DC: & 0-200mV AC.

The categories of meters that he stocks are listed down the LH side of his webpage so there's no need to trawl through all the pages to find what you're looking for.

Giorgio has the 200V DC meter:

http://www.ebay.com/itm/3-1-2-Blue-L...item5adb02609b

Also the 200mV DC meter:

http://www.ebay.com/itm/3-1-2-Blue-L...item563e4cd489

But he doesn’t seem to have 200mV AC in the same style as the other two meters.

The alternative supplier listed in the Sussex Manual (‘accessory4you.com’) has all three meters: 0-199.9V DC, (or 0-500V if preferred), 0-199.9mV DC, and 0-199.9mV AC:

They run off an AC or DC power supply, 9 – 12V and cost $8.09 USD each (about a fiver):

http://shop.accessory4you.com/05-cha...eid=51&cp_id=2

Although it may not state it in the specs, from my experience, almost all of these digital panel meters must have an independent supply which doesn't share a common ground.

(Some meters on offer on e-bay don't actually require a separate supply to operate them - they take their supply from the voltage being measured, provided it's adequate).

Hope that helps a bit.

Good luck with the project Mark!!

Scores of Sussex's must have been built by now, and many more yet to be finished.

A wonderful legacy for the late Mike Rowe, who never imagined at the outset just how popular it would become.

[Mark James]

Thank you all for your assistance.

Mark

[Mark James]

Have just gone through all the above links. They all require a 9-12V supply but the transformer from Ed has three 6V windings for the meters. I will keep looking ... no desperate hurry as I have an oscilloscope and coil winder to complete first.

Mark

[KeithsTV]

I would guess that these meters do not consume much current. If this is the case then the 6V windings can be used to drive a voltage doubler. The DC output could the be regulated with a linear regulator. The LDO type I described at last weeks Golborne talk would do and could be set to any voltage between 6V and 12V.

Keith

[Ed_Dinning]

Hi Mark, if the meters need 9-12 volts, is it DC or AC? Most of these meters specify either and have a rectifier within.
If you bridge rectify the 7v supply and feed a cap the output voltage will be
7*1.414=9.89v this should work fine at the low currents involved to drive the meters. Failing that a simple voltage doubler (2 caps, 2 diodes) will work as Keith suggests.

Ed

[Mark James]

Thanks Ed & Keith. Some specify DC only but some are also AC - they are nearly all 9-12V although a few are 5V DC with warnings about polarity of connections. I will follow your advice and probably do a separate regulated circuit for each with a voltage doubler if required. I was going to message you about the difficulty obtaining the specified meters as future constructors may wish to find meters first and then decide on the windings (9V may give more choice.)

Thanks again for your assistance. Mark

[Ed_Dinning]

Hi mark, I can certainly wind the meter outputs to 9v if requested, or add an extra winding if required, but I try to keep the transformer to the original standard so the it agrees with the Sussex documentation.
You may even be able to add some extra turns of thin well insulated wire round the bobbin in the space between the windings and the lams. Connect this series aiding and you are set up. You will need about 6 turns for an extra 2 volts.

Ed

[Mark James]

Thanks Ed - plenty of potential solutions.
Mark

[davej12a]

Mark (or Martin if he is around!)

I am interested in building this, are there any more PCBs available from Martin would you know?

Many thanks,

Dave J

[G8UWM-MildMartin]

Dave,
I have one untinned PCB available, plus another that has been promised to someone but not sold yet. (I thought I had a few more tinned ones stashed somewhere safe, but can't find them so have probably sold them!)

Which brings me to ask the participants here:

Has anyone got an improved/ corrected version that they can offer?

I'd be very happy if so and if they could take over production and supply arrangements.
Otherwise, I'm willing to help by funding a batch to their design at P&M Services.
As a last resort, if nothing is forthcoming, I'll put in another repeat order of originals at the end of the year.

Best regards,
Martin.

[Omegaman]

Mark,
The meters specified above work fine on a 6V AC supply.
No need to change or add anything.

Regards

[Mark James]

Howard,
Thanks useful to know that although specified as 9-12v they will work on 6v. Which ones did you use?
Mark

[Omegaman]

They were the usual blue LCD ones from 'Asia Engineer' on Ebay.

Regards

[squegging]

Hi All,

I started this project back in the summer of 2012 and still nowhere near finished. Various things have got inn the way. However with time to spare, I have been looking over the forum to see what developments have been made. I was thinking of laying out a pcb with all the changes incorporated, plus an 8030 grid stim oscillator, and I noticed a post for a 1.4V / 2V heater circuit using I think a LM317 regulator. I've since been pulling my hair out in desperation trying to find it again to make note of it. Can anyone please point me to the relevant post?

[mole42uk]

The complete manual is here https://www.vintage-radio.net/attach.../sussex-v1.zip - size 4MB.

The ZIP file includes a second document with details on how to print the manual.

I have added the above link to post #1.

Post 1155 and post 1 both point to the complete User Manual which contains all the updated information!

[squegging]

Thanks Richard. I knew I had seen it somewhere. A really useful manual duly noted!