Velleman DVM13MFC2U Frequency Counter - Page 1
Forum section: electronics / testgear

author: dcbrown73
author_rank: Regular Contributor
timestamp: July 27, 2019, 06:57:02 pm
content: Hi All,I've been building my hobbyist lab for a couple of years now and I wanted a frequency counter, but as of yet I hadn't had a hard reason to buy one as if push came to shove. My oscilloscope (Rigol DS1104Z+) would provide the freq in a pinch.Anyhow, given that I hadn't really had to have one yet, I really didn't want to spend several hundred bucks until I knew had to properly use one and knew it would be used a lot more than never.After reading a few reviews and the *single* 5 year old Youtube video (below) about it. I ended up purchasing aVelleman DV13MFC2U.I had a couple of questions to know what I should expect from one as it pertains to an *acceptable* accuracy and resolution.While the scope is supposed to measure from 0.01hz to 2.4Ghz. (0.01hz-50Mhz channel A and 50Mhz-2.4Ghz channel B) So far I've only measured 25mhz and below as I'm not using anything above that at this point.I have a circuit that operates right at 16.610khz and my scope vs counter where only about 0.4hz difference. The scope was at 16.6107khz while the counter counted 16.6111khz.At 25mhz (using my Rigol DG1022Z func gen) it had a 169hz variance. (scope at 25.000008 vs FC at 25.000177mhz) (so resolution was 6 digits below the mhz mark, and 0.x hz resolution at 16khz)I can't imagine this variance being an issue for me, but on the grand scheme of things. How does this compare to a FC that cost a few hundred dollars? (I likely won't ever need the ones that cost thousands)Finally, since I can't find any information about this device here in eevblog. I will post a few thoughts I've had about it given the short time I've had it. (it arrived yesterday)At $67 shipped brand new. I'm ecstatic given its ridiculously cheaper than other frequency counters on the market (the next one was 3x the price) that aren't the cheap solder your own caseless Chinese version from eBay.The variance test listed above was without letting the device warm up. (taken a couple of minutes after turning it on) I will let it warm up and retest to a) see if the measurement changes, and b) if it does. How much drift to expect, (should I always wait before taking measurements) and c) see if there is any longer term drift (after hours of being on)The counter is in a plastic box and is extremely light weight. This isn't an issue except that the device feet are part of the blow molded plastic case so it also doesn't have rubber feet to help create an anti-skid resistance. (light eight and slippery) So, you can easily push or pull it around if you're not careful. Pulling a lead a little can cause it to slide. I will look for some adhesive rubber feet or something to help keep it in place.I won't go over the features as you can find that at the link provided.So far, I'm pretty happy with it, but then again. I'm a frequency counter noob. Anyhow, if someone could provide feedback about the accuracy and resolution I would highly appreciate it. The rest is info if someone else happens to be looking at this model.Thanks,Dave

author: sab
author_rank: Contributor
timestamp: October 08, 2019, 10:23:40 pm
content: I have a counter that is the same as yours but with the model number VC3165, manufactured by Victor. There are a few videos on youtube that refer to it. I found the one by Horus interesting. He did a review and found it was just 2 ppm off at 10Mhz which was pretty good for me.Hope this helps,Sanjay