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Old 4th March 2018, 12:22 PM
Bonky Bonky is offline
Join Date: Feb 2018
Location: Sheffield
Posts: 61
Default Re: KEL84 advice -please...

Thanks Bob, and yes I do have an account.

BTW Multimeters: I have the excellent ANENG AN8002 and a cheapie ExCEL XL830L.

Somewhere in the garage is an Avometer 7. It still works except, strangely, measuring voltages! (I have cleaned all switches and replaced the internal batteries). The leads and probes are shot though.

I also have a diode/resistor/transistor/capacitor tester that works surprisingly well :

Edit: actually it was this one:

Again, many thanks for all the helpful replies and encouragement.


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Old 4th March 2018, 08:47 PM
bikerhifinut bikerhifinut is offline
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Join Date: Jan 2006
Location: Penrith, Cumbria
Posts: 944
Default Re: KEL84 advice -please...

My three pence worth:

Don't get hung up on test kit and other expensive stuff you don't need unless you are really interested in going into the radio/electronics hobby in some depth.
Just build the amp. Hundreds have been built, it's a tried and tested and nicely simple design.
Follow the destructions carefully, WD gear has very good and clear manuals.
I used to tick every stage of build off on a printout of the assembly manual.

Use the parts as supplied, don't even think about "boutique" bits or deviating from the plan.
Take your time, be as neat as you possibly can with your work. This will save a lot of aggravation should there be any teething troubles as a neat easy to follow wiring layout will make it easy to spot any howlers.
Double check your work at every stage, then check it again. OCD maybe but again in the long run it can pay dividends.

Finally, enjoy the fruits of your labour, you'll have earned it. If it sounds right it IS right. Don't go looking for problems that aren't there.

One decent multimeter is all you will need. Anything more is a bonus if you feel the need. And remember its normal to have a certain spread of tolerance on voltages on Valve gear, especially as the PSU isn't regulated so theres the variability of the british mains to account for.

the AVO 7 is a nice interesting bit of period kit but with a sensitivity of 1k/volt it isnt going to be acuurate enough without applying a correction factor. The later model 8 and 9 at 20k/volt are fine though and I started off using a fairly ordinary 20k/V analogue meter which served me well for many years.


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Old 4th March 2018, 08:55 PM
Bonky Bonky is offline
Join Date: Feb 2018
Location: Sheffield
Posts: 61
Default Re: KEL84 advice -please...

Thanks Andy; all understood.

I must mention in passing that I've been recently buying Hacker and Roberts radios on ebay and 'mending them'.(Hence the sig gen and 'scope)

Also back in the '70s I built a Lindsey-Hood amp from scratch (including etching my own PCBs) so I'm not (perhaps as I've painted - mea culpa) a complete novice, but am aware of my deficiencies!)

Thanks again to you and everyone else - and please keep the advice pouring in!


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