Multimeters

[Rats]

Ok So ive been looking into getting a new multimeter for amp repair.

What would you recommend?

Ive been looking at: Amprobe am-510, Extech ex330 and tons of others. Too many to list.

im not sure if the expense of a fluke is really needed functionality wise (or is it?)

some advice needed

[Ed_Chambley]

Fluke is certainly not necessary, however very nice.  I have an 87, but also it is very nice to have a couple.  I have actually purchased 2 from Harbour Freight and the work fine.  I use a Triplett made in 1955 sometimes.  There is some that actually prefer analogue meters.


The only recommendation I have is about probes.  I like to have a set of clip on probes for safety.  Fluke is actually making an import model:  Fluke 17B and it is around $100.  I checked one out and found it to be nice if you want something that has Fluke on it.

[Rats]

Well i have been offered some older flukes second hand that I need some help with. what one would be best? Fluke 77 original. Fluke 73. Fluke 25

[Ed_Chambley]

Well i have been offered some older flukes second hand that I need some help with. what one would be best? Fluke 77 original. Fluke 73. Fluke 25

I can only speak to the 77 as I do have one.  Very good meter and I actually found this one on the road side.  I checked it against others and it works fine.  I have seen the 77 in a pawn shop and the guy said he would take $50 for it if that helps any.

[sluckey]

Both meters you mentioned in the original post are rated for 600V. If I had to choose between them, I'd take the Amprobe. Fluke 87 is rated for 1000V. I like that. If my 87V breaks today, I'll buy another 87V tomorrow. However, you can buy many Amprobe AM-510s for the cost of a Fluke 87V.

Most any $50 meter will do all you want inside a tube amp, but most will be rated for CAT 3 (600V). So, be aware of max voltage limits.

[PRR]

I have often been happy with $3 meters. DMM technology is very mature. Mechanically, you get what you pay for. But unless you are abusive, the $3 meters last a few years, which make a $150 meter hard to justify.

I have a Fluke and a Klein, both very costly and "pro". Features I will never use.

I also have Radio Shack meters from the last century which are still fine for all amp-bench needs.

I am STRONGLY in favor of *three* meters. One meter, you never know when it is wrong. Two meters is like two watches. With three you can do a proper cross-check. Also when bringing up an amp it is wise to monitor key points for early signs of trouble. I like to at least watch main B+ and cathode current. Push-pull amp may already need 3 meters.

The slick tool is a true VTVM. Find one with probe on eBay, expect to have to replace filter caps and battery holder, and buy a spritz of good DeOxit/eqiv to clean the switch. This does not replace a DMM. Sub-Volt is small for them. The wall-grounded chassis and black lead can't be "floated" off-ground. You have to pre-plan your range, and you have to read little marks with confidence. But a needle-meter does show trends faster/better than a bobbling LCD. (Even costly DMMs with "bar graph".)

[John]

I've got a $50 Klein from Home Depot that I've used for years. It's measured 1600 volts when I was poking around inside a 'scope, and measures ohms with great accuracy. I use analog meters for many things too.

[alerich]

I'm not sure if the expense of a fluke is really needed functionality wise (or is it?)

It's not. Many swear by them. The knob broke off of mine after ten years of light use. Plastic shaft. After listening to me bitch about my dead Fluke a friend gifted me with a Greenlee DM-810 he was not using. Very nice meter and is more robustly built. I'm with PRR, though... I think the average budget meter is more than suitable for the vast majority of amp work most of us encounter.

 

[MoparWade]

It's worth considering the other things you may want to use the DMM for. I have a Fluke 87V but I use it for all sorts of projects outside of amp building.

[jjasilli]

Looks like I'm in PRR's camp to a fault .


In the center are 4 Heathkit IM-18's next to a stack of 3 Fluke 8000A's. I like the analog meters to monitor general voltages in an amp under test.  The DVM's are more handy to take specific measurements, and to take floating readings (The VTVM's can only read from test point  to ground.)  I also use, a lot, a palm size Radio Shack DVM, not pictured.


The narrow black box atop the decade box is an ancient Heathkit M-1 "Handtester" multimeter.  Don't actually use it much.  OK to monitor wall voltage I guess.

[eleventeen]

The only thing I would suggest is to NOT buy a 30 year old Fluke thinking you are saving money. The new meters have so many more features and those old ones have unquestionably seen some abuse and are fragile.

[PRR]

> are fragile.

Mine is well over 30, has varnish seepage, and works fine.

AFTER I put VERY expensive fuses in it. If the new ones auto-blow and re-set without special-ordering rare and expensive fuses, maybe I should modernize.

[eleventeen]

Hey, go for it.


You buy one of these and you'll hate life.

[jjasilli]

Maybe you had a bad experience.  But these old fluke meters work fine. 

[vibrolax]

I've gone the PRR route, as I often like to monitor several points.  I have 2 harbor freight DMM's and another cheap "Scope" DMM that's about 20 years old.  The weak point for HF meters seems to be the probes, which don't stay reliable for long at all.  Other than the probes, they have worked well for years.  I appreciate the quality and reliability of a Fluke, and would jump on a good deal if I ran across one. 
Jon

[Moonage]

I am not going to tell you what multimeter to buy, but will try to give some advice how to choose one.
First off go and check specs for some high end meters like Fluke 289, or Kyoritsu KEW 1062 and similar feature rich meters (If you can afford them $500+, go ahead  ). Write down features, and there is a lot of them on those high end meters, and make your list of the features that you NEED for amp repair. Use the list to find your multimeter. For example, I do not think that you will need Lo-pass filter used to measure voltage on VFDs,nor do you need 0.02% accuracy, but having fast continuity checker, or min/max, or LowPower-Ω measurement, might be handy. For reviews, the best place to go is probably eevblog.com.

And you do not have to get Fluke to get all those features, and safety ratings...check out Brymen multimeters -
http://brymen.eu/
http://www.tme.eu/en/katalog/#id_category=112610&s_field=artykul&s_order=ASC&visible_params=2%2C1785%2C1786%2C1787%2C55%2C1790%2C1799%2C1784%2C72%2C1794&used_params=2%3A45315%3B

Amplifiers are CAT I, maximum CAT II appliances, so category rating is not that critical, but max voltage is. If the meter is going to be used for other purposes, add that in count too.
To get better understanding of CAT ratings, check these links:

http://content.fluke.com/promotions/promo-dmm/0518-dmm-campaign/dmm/fluke_dmm-befr/files/safetyguidelines.pdf

http://ecmweb.com/content/does-your-meter-safety-measure

https://www.grainger.com/content/safety-digital-multimeter

Hope this will help