Products > Test Equipment

LC100-A : A precise LC meter for 3.75$

(1/2) > >>

JacquesBBB:
I was lacking a device to measure small caps and I came across this incredible deal  on ebay

http://www.ebay.fr/itm/111926481261?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

I  took the chance, order it on  May 17, for 3.75$ including postage, and just got  it today. It is provided with a decent usb cable, alligator hooks, and seems to work just fine

Here are some examples of  measure  of 1% caps I have.

A                          B         (A-B)/A
nom.         prec.  meas.     
value
(pf)         

33        1%    32.65          0.011
3300     1%    3290           0.003
22000   1%    21950         0.002
10000   1%    9964           0.004

I  have also  some old caps of lower values

A                          B         
nom.               meas.     
value
(pf)         

12                      12.68
15                      15.35
18                      18.84
27                      27.54


I must say that I am perfectly happy with this device which is based on STM8S103.

lukaq:
what the?? how is it that cheap? and most countries are excluded from sending to

PedroDaGr8:
looks to be a typo. Already all sold out, seller now sells them for $14.

JacquesBBB:
Yes you are right,  they probably made a mistake in the price when they put it at $3.75.
They were  fair to send it  anyway.

I  have measured some coils and  seem to have problems for low inductance values

for the same  transformer coil,
I get  11.73 mH on the HiL scale and 754 uH  on the normal scale. Any hint ?

My guess is that the 11.73 mH is the right value as the primary gives 4.47 H and this is a  240V/12V  transformer,
so I expect that the ratio of inductance will be roughly 400 (20^2).

elecdonia:
It’s time to either bump this old thread in a major way or start a new thread for the LC100-A inductance/capacitance meter.

The LC100-A is widely available from many vendors. Typical price is now $15-25 USD.  It is worth every penny!

While many LCR meters are offered by major test gear manufacturers, most are at least 5-10 times more costly than the LC-100A.

The LC100-A is a great companion to the $20 Transistor Tester devices which many of us already have on our workbenches. A C or L which is difficult to measure accurately with one of these devices might be measured more accurately by the other device. This is because the measurement technology is entirely different for Transistor Tester vs. LC100-A.

I have been using the LC100-A for several years. It is incredibly useful for projects containing inductors, such as switching power supplies and audio loudspeaker crossover networks. It is equally valuable for RF projects, especially when tuned circuits need to be measured. I first obtained an LC100-A to help me diagnose and restore vintage AM/FM broadcast band radios. This task frequently requires accurate measurement of very small C (1-500pF range) and also small L (5 to 500uH).

I will begin by posting links to several detailed discussions of the LC100-A:

The following thread from the Antique Radio Forum is a good starting place:
     antiqueradios.com LC100-A, LC200-A, and similar low-cost digital LC meters?

The LC100-A has also been discussed in these other EEVblog topics:
     EEVblog Other Equipment & Products board: china-lc200a-lc-meter-teardown
     EEVblog RF, Microwave, Ham Radio board: microwave-tl-coax-impedance

Other links to the LC100-A:
     VK4GHZ.com LC100-A LC meter mods
     ludens.cl Understanding, fixing, and improving the LC100-A
     Hackaday.io LC100A LC meter fix

This link describes a comprehensive redesign of the basic LC100-A circuitry which adds capability to measure Q of tuned circuits:
(in German but Google will translate)
     the-dg5mk-lcq-meter-v-2.3

Another home-brew version is described in the next link. It uses the Atmel ATmega8515 MCU. The ATmega328 could easily be substituted.
     http://uzzors2k.com/index.php?page=lcfmeter

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod