[Lowfer] Re: LRC Meter

[Clint Turner]

Although it doesn't do the "R" part of LCR, one good, small cheap meter 
for measuring very small L and C is the AADE L/C Meter IIB (www.aade.com).

If one is very careful, measuring to 0.1pf and 10 nH is perfectly 
reasonable (lead precautions, etc.)  For small L and C it's measuring 
frequency is in the 100's of KHz range.

It only goes up to several hundred mH and a couple uF (it doesn't do 
electrolytics, but that's not a range where I'm likely to find or need 
precision caps anyway...) but if properly calibrated (the one precision 
component is trimmed) it has an accuracy better than 1% - at least when 
I checked it against an assortment of precision L's and C's kicking 
around.  In comparing it with my old General Radio 1650A, it agrees as 
closely as one can read the dial. 

The 1650A does read D with 0.001 divisions, at 1 KHz.  According to the 
manual, the device is usable up to 100 KHz or so - but the accuracy 
starts to suffer above 10 KHz or so.

Just for yuks I measure a (pseudo)random assortment of caps with the 
1650A, I noted the following D readings:

A cheap 0.1 uf Z5U disk ceramic:  0.015
A high-quality 10nF dipped silver mica cap:  0.001
A WWII vintage "100 MMF" postage stamp mica:  0.0025
A 1 nF polystyrene cap:  <0.001 (maybe 0.00025 - if you believe the dial 
and squint at it...)
A 2.2 uF mylar cap:  0.004
A 4.7 nF ceramic, line bypass:  0.0065
A 150 pf monolithic chip:  <0.001 (0.0004, maybe?)
A 150 pf polystyrene:  <0.001 (0.0008-ish)
A 150 pf NPO ceramic disk:  0.001
A 150 pf N150 ceramic disk:  0.0025
A 150 pf monolithic chip:  <0.001 (0.0004, maybe?)
A 150 pf polystyrene:  <0.001 (0.0008-ish?)
A 150 pf NPO ceramic disk:  0.001
A 150 pf N150 ceramic disk:  0.0025
A cheap 150 pf ceramic disk of unknown quality:  0.015
A cheap 150 pf ceramic disk of unknown quality:  0.015

Clint
KA7OEI