Retired due to poor health

[mikeyb]

The devil and idle hands eh

[Colin Wonfor]

Well now forced to stay indoors and my pit I can do some R&D work so first project is a volume control using optics.
It will allow us to have any value and multi channel pots at any pre-fixed value i.e. 10R-1000MR and either Log/Anti Log or Linear well any curve you want basically.
The track sliding noise will go away and matching can be between 20% to 0.01%.
It can also be driven with a voltage reference or a R2 Ladder. The ref/control voltage will be set to 1.00V to 5.00V but with a simple attenuation network this could also be changed.
Pre-set lower and upper limit can also be set i.e. 158R Min to 1099R Max
The pot will have upper and lower BW limits 1Hz - 400KHz but special can be made.

PCB for this unit will be available from me or ABCaudio.
The unit can also be master slave configuration. For mixer and motor control references.

So watch out for it.

[tankertop]

Probably the wrong thread (mods: please move if inappropriate) but just thought I'd ask a quick question of you, Colin. I own a sample of the prototype Class A amp I think you designed (for Arcam?). Just changing out the 4.7uf/63v axials (all, unsurprisingly, out of spec now).

Usual hassle with lifting traces but all done now but for one remaining axial (shown in last pic). Appears it's either in the wrong way around or the PCB is incorrectly marked for positive. Looks original. I know it was a squillion years ago but you wouldn't happen to recall which is the more likely?

DSC05999 by Brer Rabbit, on Flick

DSC06012 by Brer Rabbit, on Flickr

DSC06012 (1) by Brer Rabbit, on Flickr

[Colin Wonfor]

Probably the wrong thread (mods: please move if inappropriate) but just thought I'd ask a quick question of you, Colin. I own a sample of the prototype Class A amp I think you designed (for Arcam?). Just changing out the 4.7uf/63v axials (all, unsurprisingly, out of spec now).

Usual hassle with lifting traces but all done now but for one remaining axial (shown in last pic). Appears it's either in the wrong way around or the PCB is incorrectly marked for positive. Looks original. I know it was a squillion years ago but you wouldn't happen to recall which is the more likely?

DSC05999 by Brer Rabbit, on Flick

DSC06012 by Brer Rabbit, on Flickr

DSC06012 (1) by Brer Rabbit, on Flickr

I am pleased to say this is not my PCB design, sorry.

[tankertop]

I am pleased to say this is not my PCB design, sorry.

Ah, one of THOSE. All understood...

[Firebottle]

Measure the voltage across the cap, could be next to nothing, then fit the new one to suit the polarity.

[tankertop]

Measure the voltage across the cap, could be next to nothing, then fit the new one to suit the polarity.

Will do, thanks.

[iansr]

Well I can,t stop thinking of designs.
So I am now keeping my retired old brain busy, the first is a SECA Twin Headphone Amp with two DAC,s
Then I will go back to my favourite non audio love, yes you guessed it chocolate, NO PSU designs working on a ultra low noise low impedance range. 3.3V,5V and + & -12V.
And a mains conditioner using a pure sine wave and a large analogue amp about 1KW. You can adjust the frequency 40-400Hz and the output voltage from 80VAC to 260VAC using the meters on the front. Plus a fixed 10ppm 50HZ switch.
Then on to special carbon fibre metal plating techniques, plating with Copper, Nickel and Gold.

All looking good so far and no magic smoke, nice.

There is definitely a market for low noise LPS’ with high output current capabilities for powering audio PCs.

[Colin Wonfor]

A experiment, NOT TO BE DONE AT HOME BOYS AND GIRLS
I got some of the EWA IC cable which has four conductors and a shield,
Tested the break down voltage at 2500VAC between all.
OK the wire could handle about 3Amps max.
Made a simple cheap and nasty MK plug and Bulgin IEC lead 2 M long.
And tried it on the New Oberon I have, based on the M50 and M50P mixed (only 3 ever made cost to high)
We have one my sons Sam and Scott have one each.
It was fantastic the cheapo Woolworth IEC was crap in conclusion.
Just a fun and dangerous things to do under lockdown.
Still waiting for Solar Panel from space Mike, phew

Keep well all.

[Colin Wonfor]

Well so far the retirement has gone well, ha ha, not a chance I have been more busy doing more designs than ever before. This include new cable idea and construction, so I decide to retire at 99yrs 364 day, just to keep busy.
I love walking and the last year that was not possible, that is due to my health state and has not been a good idea so into my pit I go now 7 day a week .
I have had few interest bangs I managed to blow up a 1600V 300A IGBT, the beast was 4 x 3 x1.5 inches approx and the smoke escaped blowing it lid off and the 5mm connector bolts.
Thank good I have few more, I was building a 400V 100A charger. Clocking at 50KHz I only had to find lots of mobile phone bats to make it work. I need 80 of 5V 2500mA per Cell block and I need 50 blocks. So has any body got 4000 mobile phone batteries?