Iso-Tech IDM 305 DMM (under the hood)

[jucole]

For anyone interested.

[SeanB]

Love the sleeving on the fusible resistors and PTC's to keep the smoke in.

[jucole]

One of the interesting features of the 300 series is they claim it to be self-calibrating,  I've no idea how that works and would interested to know how they do it.

[robrenz]

It looks like no gold on the switch traces. 

[jucole]

It looks like no gold on the switch traces.

I believe it's berylium copper contacts

[robrenz]

It looks like no gold on the switch traces.

That would be what the switch fingers are made from but the circuit board looks like plain copper.

[jucole]

It looks like no gold on the switch traces.

That would be what the switch fingers are made from but the circuit board looks like plain copper.

maybe it's just the bad pictures I took. Here is the feature list from the manufacturers website.
http://www.appatech.com/appa_product_fea.php?pdid=20051219052439826951&&kindid=2005081003113623241

[robrenz]

I am not trying to say this is a bad meter it actualy looks pretty well made, and the website does say gold plated circuit board for the switch. I could be wrong but I see your fourth picture showing gold plating on the switch area and your second and third picture clearly being bare copper. If you tell me that picture 2 and 3 look just like picture 4 in the switch contact areas when viewed in person then I am wrong and all is well.  If not, then you should ask for a new meter that has gold where they said it does.

[jucole]

hi, I think it looked like the pcb was gold in places then silver where the components were soldered on. The meter I bought new from Ebay for £85 so it was a bit of a bargain, much better than my
UNI-T 70B, so a step up the ladder! but compared to others at the £240 price tag, perhaps not in the right direction ;-)

[Fraser]

I have bought several Iso-Tech meters and I must say I have been pleased with them. I have the 303 and the 305 in my inventory and they appear very well made. Their accuracy appears to be on a par with my two handheld Fluke's (77 I and 87 III). I also have the Iso-Tech IDM17 probe meter that comes with a current clamp head that replaces the test leads....a very neat design. I bought the IDM101 and 105 very cheaply at the same time and they are of decent quality as well.

Iso-Tech branding moved from grey/red cases to dark grey/green cases in 2010(tbc) and a lot of the grey/red meters became available on ebay as NOS at really wallet friendly prices. RS appeared to just dump them on the surplus traders for disposal. My 305 cost me GBP60 and the 303 was only GBP30 delivered  All were new in their boxes but no warranty.

Fraser