Amidon Type 2 Cores

[HUGH]

In theory Amidon type 2 iron-dust toroids have a red and plain coating. Looking at those for sale, on Ebay for example, they are now brown and plain, I have bought one or two and can't tell if they are genuine or if there's been a change by the manufacturer. Does any Islander know or can confirm there has been a change?

Amidon tan coloured torids phenolic and have no magnetic properties.

[PA5COR]

Having several of them bought over the years, from 200 to 400 size, i can confirm the colour became much more dark, almost red/brownish.
Put a few windings on an older one and newer one and see how much micro Henry they make and see for yourself.

[kb2vxa]

Excellent idea, I'm reminded of core grading on my last job where reading low inductance values with a Boonton 1MHz L bridge inductance of the wire itself became an issue. I used a 3" length of 16ga straight bus wire between the terminals without a problem. Now the question is where to find laboratory equipment on the cheap?

[PA5COR]

Can't help with the laboratory equipment, though measuring equipment became a lot cheaper over the years here, more on offer 2nd hand, less interested party's to buy it i guess, one benefit our dying out hobby has it seems.

[N8YX]

Now the question is where to find laboratory equipment on the cheap?

eBay.

A lot of this stuff you can't give away if it doesn't have USB/Ethernet control capabilities.

[HUGH]

Thanks 'COR that's reassuring.

[PA5COR]

my 4 x 100 MHz scope cost an arm and leg and an extended loan on your house 10 yeears back, now they are on 2nd hand sites for near old iron price.( 100 Euro Le CroyLA314 400MHz 4 channelBewaar (https://www.tweedehands.nl/zendamateur/zend-ontvangapparatuur/meetapparatuur/croyla314-400mhz-4-channel-500185067.html?csrf_token=7tZ6Lum4g6JAG2f3R3Tb&bewaar=1)
€ 100,00





Go figure....

[N8YX]

my 4 x 100 MHz scope cost an arm and leg and an extended loan on your house 10 yeears back, now they are on 2nd hand sites for near old iron price.( 100 Euro Le CroyLA314 400MHz 4 channel

Bewaar (https://www.tweedehands.nl/zendamateur/zend-ontvangapparatuur/meetapparatuur/croyla314-400mhz-4-channel-500185067.html?csrf_token=7tZ6Lum4g6JAG2f3R3Tb&bewaar=1)
€ 100,00
Go figure....
I have a spare Tek 7603 with 2 7A26 vertical amplifiers and a 7B53A timebase that I'm going to list soon. Get a 7L12, 13 or 14 and turn it into a 2GHz spectrum analyzer - and there's a lot of other plugins besides. As configured it's a 4ch, 100MHz delayed triggering scope.

But it's largish and can't be remotely controlled or programmed, so the average experimenter will simply pass the thing by.