Will this do what I need for tube amping? Or is it a 'wannabe' meter?
A handheld digital multimeter for measuring DC and AC voltage, DC current, Resistance, Diode and Transistor with battery operated
Blue backlight - good for use in dark
Thick rubber casing protects the multimeter from splashes and minor bumps
Test leads and 9V battery included
Low power requirement with auto power off
Data hold function
Continuity beeper
Specification:
DC Voltage: 200mV/2V/20V/200V ±0.5%, 600V ±0.8%
AC Voltage: 200V/600V ±1.2%
DC Current: 200?A/2mA/20mA ±1%, 200mA ±1.5%, 10A ±3%
Resistance: 200?/2K?/20K?/200K?/2M? ±0.8%
Display: LCD, 1999 counts
Fuse protection: F-200mA/250V
Operating Temperature: -0C to 40C
Overrange Indication: Only figure "1" on the display
Polarity Indication: "-" displayed for negative polarity
Low Battery Indication: - /+ display
A handheld digital multimeter for measuring DC and AC voltage, DC current, Resistance, Diode and Transistor with battery operated
Blue backlight - good for use in dark
Thick rubber casing protects the multimeter from splashes and minor bumps
Test leads and 9V battery included
Low power requirement with auto power off
Data hold function
Continuity beeper
Specification:
DC Voltage: 200mV/2V/20V/200V ±0.5%, 600V ±0.8%
AC Voltage: 200V/600V ±1.2%
DC Current: 200?A/2mA/20mA ±1%, 200mA ±1.5%, 10A ±3%
Resistance: 200?/2K?/20K?/200K?/2M? ±0.8%
Display: LCD, 1999 counts
Fuse protection: F-200mA/250V
Operating Temperature: -0C to 40C
Overrange Indication: Only figure "1" on the display
Polarity Indication: "-" displayed for negative polarity
Low Battery Indication: - /+ display
Looks OK - How much are you going to pay for it? Personally, I would like auto range resistance and volts. Have a look at the Chinese manufactured flukes on ebay - I think that you could pick up a decent meter with auto range and capacitance for about AUS 100. Check out this for example -
http://cgi.ebay.com.au/Fluke-17B-Mu...yZ105805QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
http://cgi.ebay.com.au/Fluke-17B-Mu...yZ105805QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
If you guys haven't worked out already, I'm not only new to valve amps, I'm also new to electronics. I'm 41 and trying to get my head around some concepts that baffle me, mainly because a lot of the 'noobs start here' links take for granted the reader has a basic knowledge of electronics or, the reader knows the purpose of each component.
Therefore, I spotted some DIY DVDs that guide you through a build project and they reckon other than metal/wood working tools, you only need a multimeter.
Therefore, I spotted some DIY DVDs that guide you through a build project and they reckon other than metal/wood working tools, you only need a multimeter.
If it is around $20 I would say go for it. What you will REQUIRE to get as well will be a set of leads that either have alligator clips or those little spring loaded retractable clips. You do NOT want to be holding on to those probes around the voltages you will be measuring. One slip and you may fry yourself or your project.
And read this http://www.diyaudio.com/forums/showthread.php?s=&threadid=30172
The voltages in these things are very dangerous! Even the charge stored in the capacitors when the power is disconnected is dangerous!
Having said all of that, my dad (an electronics engineer) used to build tube gear in his youth. He came from a background of having very little money, and his first projects were completed with salvaged parts without the use of any test gear, he did not even have a multi-meter.
I have a few multi-meters, but tend to use the cheap ones initially in a project, because if something is grossly wrong, it is better to blow up a cheap multimeter than an expensive one! I have something like this that I use regularly http://www.dse.com.au/cgi-bin/dse.storefront/474031cb04fc84c4273fc0a87f9c071d/Product/View/Q1469
Yes, I can only get readings for the heater voltage to one decimal place, but if it says 6.3 V I am happy! I have a mid-priced auto-ranger that I use frequently too, and also an old Fluke that my dad gave me that I use less frequently - don't want to wreck it!
Hope this helps, and good luck!
Chris
And read this http://www.diyaudio.com/forums/showthread.php?s=&threadid=30172
The voltages in these things are very dangerous! Even the charge stored in the capacitors when the power is disconnected is dangerous!
Having said all of that, my dad (an electronics engineer) used to build tube gear in his youth. He came from a background of having very little money, and his first projects were completed with salvaged parts without the use of any test gear, he did not even have a multi-meter.
I have a few multi-meters, but tend to use the cheap ones initially in a project, because if something is grossly wrong, it is better to blow up a cheap multimeter than an expensive one! I have something like this that I use regularly http://www.dse.com.au/cgi-bin/dse.storefront/474031cb04fc84c4273fc0a87f9c071d/Product/View/Q1469
Yes, I can only get readings for the heater voltage to one decimal place, but if it says 6.3 V I am happy! I have a mid-priced auto-ranger that I use frequently too, and also an old Fluke that my dad gave me that I use less frequently - don't want to wreck it!
Hope this helps, and good luck!
Chris
UModel : Uni-Trend UT33B
DC Voltage : 200mV / 2000mV / 20V / 200V / 500V (+/-0.5%)
AC Voltage : 200V / 500V (+/-1.2%)
DC Current : 2000mA /20mA / 200mA / 10A (+/-1.0%)
Resistance : 200W / 2000W / 20kW / 200kW / 20MW (+/-0.8%)
DC Voltage : 200mV / 2000mV / 20V / 200V / 500V (+/-0.5%)
AC Voltage : 200V / 500V (+/-1.2%)
DC Current : 2000mA /20mA / 200mA / 10A (+/-1.0%)
Resistance : 200W / 2000W / 20kW / 200kW / 20MW (+/-0.8%)
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Probably any of these will work fine to get you started in your new hobby endeavors (welcome!). I've been very impressed with the cheap Chinese-made meters that I've bought recently. I have a couple of laboratory-grade Fluke and HP 6 1/2 digit bench-top meters for precision work. But the cheap meters are surprisingly accurate when compared to these big guns. You should not need to spend more than about $20US for a usable "starter" meter. I have bought several, including some $2.99US throw-away DVMs for monitoring auxiliary voltages. I sometimes will have three or four meters connected to simultaneously monitor voltages in an audio project. If a cheap meter fails (not very common) I simply toss it over my left shoulder and grab another one. The big Flukes are very nice, but you don't need anything that fancy or expensive to get started. The only upgrade feature that I might suggest is auto-ranging, as someone else mentioned. This means that the meter will find the right voltage and resistance range automatically. As long as the voltage being measured is less than 1000 VDC or 750 VAC (typically) the meter won't over-range or be damaged. Some people will suggest that if you don't know the approximate range of the voltage about to be measured and can't then set the range manually, you have no business sticking probes into a chassis. These are usually people who grew up using manual range-setting meters and don't like change. My advice on tube chassis work is to assume that everything is at high-voltage. I put an alligator clip tip on the negative ("ground") lead and attach it securely to a chassis ground. That frees up one hand. Keep both hands clear of every electrical point in the chassis. One hand holds the probe carefully, the other "is in the pocket" or on the lap, etc. Then the auto-ranging comes in as not only very convenient, but perhaps as a safety feature, since you don't have to set the probe down and reach for meter over and over again, especially if the other hand is making a pot adjustment. You can stay focussed on what you're doing and on safety. That's just my point of view, coming from many years of exerience.
Morgan Jones makes a big point in his fine book "Building Valve Amplifiers" about meter speed - how long it takes the DVM to settle on a reading. Auto-ranging will prolong the readings a bit as the meter finds the right range. To me fast settling is another good want-to-have feature, but I think you can live with the basic speed of most cheap DVMs for now. I'm rarely bothered by the settling times of my cheap meters. Here in the US, we have a Chinese tool importer called Harbor Freight. They occasionally offer, on sale, a large Fluke-styled hand-held DVM with auto-ranging, frequency counter, capacitance meter and other features for $19.95 US. The secondary features are so-so, but the basic voltage and resistance accuracy is quite good. I bought four of those. My big name-brand meters have been seeing less usage.
Morgan Jones makes a big point in his fine book "Building Valve Amplifiers" about meter speed - how long it takes the DVM to settle on a reading. Auto-ranging will prolong the readings a bit as the meter finds the right range. To me fast settling is another good want-to-have feature, but I think you can live with the basic speed of most cheap DVMs for now. I'm rarely bothered by the settling times of my cheap meters. Here in the US, we have a Chinese tool importer called Harbor Freight. They occasionally offer, on sale, a large Fluke-styled hand-held DVM with auto-ranging, frequency counter, capacitance meter and other features for $19.95 US. The secondary features are so-so, but the basic voltage and resistance accuracy is quite good. I bought four of those. My big name-brand meters have been seeing less usage.
PS: For most hobby tube work, extreme accuracy is not necessary. I wouldn't necessarily pick a meter with 0.5% DC accuracy over one with 0.7% accuracy, for example, if the the latter had other good features, like auto-ranging. Most modern DVMs meters use a laser-trimmed chip for most internal functions, and that foundry tweak is very precise. I often see accuracy that is far better than specified (or needed). I measured a lab-standard reference 20K resistor a couple of days ago with one of my $19.95 meters and it was "off' by a mere 0.15%. Not to worry.
Accuracy isn't very important for audio work. People used 5% needle type meters forever with no problem, so being below 1% is just icing on the cake. All the classic tube amps were probably designed using things like the old RCA Senior VoltOhmist and Simpson 260s. Low level AC ranges down to under a volt are desirable, as is autoranging. If I had any of those cheap meters, I'd really miss my ancient Fluke 77. OTOH, when starting out, almost anything will do. If you have zero test equipment other than a meter, it's nice if it can check capacitors. I've never found any use for a meter type hfe test, using the diode check function most of the time. In order of importance on my bench, and it will be different for everybody, would be DCV & ohms, diode check, capacitance check, then AC volts. If you really get involved, you'll want some kind of scope very quickly!
Another 2 centimes from me!
I have a Maplin digital multimeter that cost about £30 I think. It's called "Precision Gold" and features the following ranges:
DC 200mV/2V/20V/200V/600V
2mA/20mA/200mA/10A
All these are available at AC just by using a slider switch.
Resistance: Diode check/200 ohms/2K/20K/200K/20M
Capacitance: 2000pF/20nF/200nF/2µF/20µF
Frequency "lo/hi"
HFE NPN/PNP
I shouldn't add this but when testing a PSU for my 813 amplifier, I read 1120V on this meter without problems.
I also have an AVO VIII that I bought for £15. With this I can read up to 2.5kV. It is 20k/V and all the classic British amplifiers were probably built using Avos.
Finally for £30 I bought a S/H Solartron auto-ranging bench digital meter. I actually had three of these, but sadly times have changed. This is super accurate: I was able to check it with a Weston cell: it was about 0.0005V out!
SO the message is that there are bargains to be found
7N7
I have a Maplin digital multimeter that cost about £30 I think. It's called "Precision Gold" and features the following ranges:
DC 200mV/2V/20V/200V/600V
2mA/20mA/200mA/10A
All these are available at AC just by using a slider switch.
Resistance: Diode check/200 ohms/2K/20K/200K/20M
Capacitance: 2000pF/20nF/200nF/2µF/20µF
Frequency "lo/hi"
HFE NPN/PNP
I shouldn't add this but when testing a PSU for my 813 amplifier, I read 1120V on this meter without problems.
I also have an AVO VIII that I bought for £15. With this I can read up to 2.5kV. It is 20k/V and all the classic British amplifiers were probably built using Avos.
Finally for £30 I bought a S/H Solartron auto-ranging bench digital meter. I actually had three of these, but sadly times have changed. This is super accurate: I was able to check it with a Weston cell: it was about 0.0005V out!
SO the message is that there are bargains to be found
7N7
Fauxpas,
I have one multimeter similar to the first one you show, except it doesn't have backlight. I bought it for 5 or 6 euro (they are almost the same price as a PP9 battery!).
It only bothers me on one aspect: when you are using the continuity test (bip signal) it takes one second or so to beep, unlike an old DVM I have that beeps instantly (like a switch operated bipper).
Go for the first one, it's pretty good for tube work and to get you started in electronics.
Welcome to the hobby!
I have one multimeter similar to the first one you show, except it doesn't have backlight. I bought it for 5 or 6 euro (they are almost the same price as a PP9 battery!).
It only bothers me on one aspect: when you are using the continuity test (bip signal) it takes one second or so to beep, unlike an old DVM I have that beeps instantly (like a switch operated bipper).
Go for the first one, it's pretty good for tube work and to get you started in electronics.
Welcome to the hobby!
Lately I have been doing the following mod to my cheap meters... renove the 9V battery, and wire in a 9V transistor battery (those big box types used in older radios).
It makes the meters much more "decicive" in comming up with a final measurement, also better for getting repeatable results when doing long measurement sets, like matching resistors etc...
Still absolutely useless for measurements close to upper and lower extremes...
Have been thinking one can daizychain low value resistors in one of those matrixblock thingies, then apply a small voltage over the extremes and compare voltages from resistor to resistor...
It makes the meters much more "decicive" in comming up with a final measurement, also better for getting repeatable results when doing long measurement sets, like matching resistors etc...
Still absolutely useless for measurements close to upper and lower extremes...
Have been thinking one can daizychain low value resistors in one of those matrixblock thingies, then apply a small voltage over the extremes and compare voltages from resistor to resistor...
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