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Yup, you're right! I can't even go by the 5% tolerance values I gave! Sorry, looks like this LC100A meter may indeed be defective. Steve

Steve the LC100A meter is reading the cap at 292.9pF, which is not within 5% tolerance.? ?That info is from the picture.? ?Doug Hendricks

Thank you everyone for the great ideas.? If nothing else you have convinced me to keep this and figure it out.? Unfortunately it will most likely sit on that shelf until I have more bench time in

Doug W Not much in these things but an oscillator, a frequency counter and some easy math. I mentioned a simple instrument that makes an L or C measurement, and renders answer in Morse code. It does

Hi Doug, The problem is you don't know what your test capacitor's value really is. You say the cap is 5%, so that could make it 313.5 to 346.5 pF,? and both meters read? the cap within that 5%.

Try this https://ludens.cl/Electron/LC100A/LC100A.html It is very interesting and I think you are a perfect candidate for his process.? Please let me know how you get along.

I bought a no name LC100a on aliexpress figuring it was worth the risk as they offered free returns.? Unless I am really missing something, it looks like I will be taking them up on the free

I must have missed your initial post. I don’t want to dismiss your feelings about LTSpice, but in my experience it is one of the easier Spice flavors. I may have to put this into perspective, my

I am getting a PeakAtlas LCR45 meter tomorrow because between that and the DE-5000, it was less costly.. I will have to get some +/- 1% caps and measure though. -- Ramakrishnan VU2JXN

Dave - I gotta say, getting a "neat-looking build" compliment from you made my day.? Thanks!? :)? ?The variable caps came from a stash of Tektronix parts that I accidently acquired when I bought

IF you want a more interesting mechanism see https://qrpbuilder.com/pto_mechanism Its a kit of board that duplicates a lipstick mechanism. That eliminates the screw moving in and out of the

Rewind old inductors! Over the years, before being displaced by LEDs, I had been collecting defunct CFLs. One immortal component is their EE-core choke (ballast) in series with the tube. At least in

other actie mixers used for DCRX over the last 50 years include: Dual gate mosfets (BF998) Simulated dual gate mosfet using a pair of cascade wired J310s SIngle ended mixer using J310 Single ended

Examples of passive mixers are diodes and sometimes mosfet. Most common examples of active mixer are Gilbert Cell which is in the common ne602/sa612 which use an array of transistors or dual gate

Hello, I remember some message on this group where someone said a DCR that was designed by Chuck Adams had an active mixer in it instead of a passive double balanced diode mixer as you would normally

Sorry for the off-topic. Consider using Sallen-Key active filters. A couple of examples using BJTs rather than opamps are below. Simply cascading 3 identical

It's a clever circuit alright, and I guess I'll have to give it a shot too. Some years back I was discussing how to measure Ft with Glen Weinweber. I think he got a little further along than I did.

Not a direct answer to your question, but ... yes, LTspice can be tough but probably no more than any other true SPICE package. I've presenting an introductory talk on the subject at FDIM. I'm not a

I've been winding my own 88mH inductors on pot cores from Amidon using their PC-2213-77 cores.? For 88mH I think it took about 100 turns.? The wire is wound on a bobbin, so it's not like putting

Yep, it's a 5 ohm resistor in parallel.? The circuit on the web has two 10 ohm resistors in parallel. I'm thinking of going with a RF voltmeter instead of the scope.? I get some 'jitter' on the max