My Fluke 27/FM is also AC coupled. You can get one used very cheap.
My Fluke 27/FM is also AC coupled. You can get one used very cheap.
Damn, those things are going cheap now! (if you live in the USA and don't have to pay $150 shipping)
A similar test using the Yokogawa TY720.
https://youtu.be/4aCN-uLeO5s?t=3162
Interesting meter the TY720, seems to be AC-coupled when on AC ranges (User Manual p.71) yet still capable of AC+DC
Interesting meter the TY720, seems to be AC-coupled when on AC ranges (User Manual p.71) yet still capable of AC+DC
The AC+DC is usual done in the DC position.
I bought mine several years ago when someone probably got a massive batch and were selling them for even cheaper. Mine came in really great condition, but someone took the effort to remove the sticker in the back with the serial number and all other details about the unit... (??!??)
I bought mine several years ago when someone probably got a massive batch and were selling them for even cheaper. Mine came in really great condition, but someone took the effort to remove the sticker in the back with the serial number and all other details about the unit... (??!??)
Me too.
I think that was when the US Army was switching to a new model or something so they were dumping them from their stores. Mine was untouched old stock, apart from a US army calibration sticker (which it still wears proudly). I think I paid about $75 with shipping. International shipping from the USA has gone up massively since then, and the eBay "Global Shipping" has made things even worse, not only is it more expensive but they garantee you pay taxes (and I'm sure they skim money off the tax, they don't give you any VAT paperwork and I'm sure they aren't paying full rate in Ireland).
Any idea how low of voltage you actually need to measure and what frequency range? I would have thought a scope would work better for what you were describing but I'm still a bit confused about what you are up to.
I work with musical instrument amplifiers, servicing, modification and restoration of vintage tube equipment. I use an AC-coupled meter to get a quick idea of the condition of the filter caps in power supplies.
Basically I measure power supplies range from 250VDC upwards into the 700VDC range. While lower voltage negative bias supplies are below -100VDC. The over-riding AC ripple component is anywhere from 15mVAC to 6VAC depending on what stage of the power supply I am measuring. Frequency is all line related 120HZ
With old bad caps the amount of ripple will be several times greater than a known acceptable amount. I then proceed to re-cap the amp or make an estimate of the repair. I am not concerned with an accurate picture of the ripple and noise, if I were I would certainly use a scope, but rather with a quick analysis as to whether parts need replacement or whether I should look for a problem elsewhere. I will use a scope to look at the audio while doing this, but power supply and bias voltages are more quickly measured with meters, otherwise I'll be forever tweaking range and position controls.
AC-coupled meters work perfectly well for what I do, but not at the price of a new scope. So i'm hoping there is a more modestly priced Asian alternative. Meanwhile, I'm making a series capacitor box.
So nothing really radical. The higher class DC coupled meters would be fine if using their voltage function but their cost is really the issue?
Now that we know it's a problem with price, you brought up $100 in 95. That's $165 in today's dollars. Is this your budget for a single meter?
Now that we have an idea on price, there may be some cheap meters that will do what you want. Did you not like the Fluke 17B? I have the 17B+ and that thing is really solid. IMO, the one shortcoming that meter has it that it's averaging. Do you need TRMS? Narrowing the choices....
I am still wondering which Brymen meters are AC-Coupled. Anyone have a clue?
The first issue that I have is whether the 17B+ is ac-coupled in the millivolt range, other Fluke models like the 117 are not.
I couldn't find a Brymen meter that has mVAC coupled, but the BM857 I mentioned before has enough resolution for your range of measurements in VAC, is decoupled and falls into your budget.
https://www.tme.com/us/en-us/katalog/?search=bm857
That wouldn't have the feature you are looking for, but it will certainly solve your problem. And you will have an excellent meter in your hands!