audio-talk

Tested on black gate wkz and parafeed choke .

Just arrived after ordering before lockdown (somehow misplaced my Hameg!

Seems to measure correctly. Stupidly cheap £9.98

Cant tell you what max range is as the sales blurb is so dumb it uses mF like a lot of idiots in the diy community. Which should be millifarrads and the wallys use it to signify microfarrad. These Chinese sellers say 100mF but as you see it measures 200 microfarrad at least. This choke is the most inductance choke I have and it managed with that. blooming bargain.

Ordered it for when I wind my 500mA chokes. The iron lams quote came in Lams alone are costing £60 per choke plus carriage bobbins £2.75, but I have to order copper elsewhere. Materials could end up £100 per choke but what do you expect great big boat anchors they’ll be. I’ll use that parafeed choke (wound yonks ago probs 15 to 20 yrs.) only one parafeed choke in the amp Stephies specified 20h. I think in this case more is better.

Serious iron, at 5.75 kg iron each choke, double that for copper then more weight again for potted in sandy pitch. I’ll use sandpit sand which is fine grains and kiln dried.

There’ll be no compromises.

As Fred Dibnar said , one mistake and it’s a day out with the undertaker.

I've had the same one for years Paul. I think its ok and a bargain compared to a 'proper' one

Yes, the Hameg Ive misplaced cost a couple of hundred and does no more. I suppose there are shortcuts in circuitry using modern components that make them both accurate and cheap.

But actually when I test the inductance of chokes I do it by calculation with dc current applied which is lower inductance if the weight of core and gap is not adequate. there are rough assumptions to guess it but the way I do it is use the choke in a filter and calculate the i inductance in the same dc current as its wound for. I made a spreadsheet calculator for it decades ago. If it was a transformer not a choke you can simply apply dc current to the secondary adjusted to turns ratio, and measure the b+ side inductance with this gadget.

Paul Barker wrote: ↑Tue Aug 11, 2020 5:59 pm
Seems to measure correctly. Stupidly cheap £9.98

Is this the LC100-A on eBay?

yes

Thanks! I shall go and get one in due course