auto ranging dmm

mike langer · 2019

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Offline mike langer

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on: June 26, 2016, 08:38:43 PM
I have a self ranging digital mm.will this work for my crack build?Thanks



Offline Doc B.

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Reply #1 on: June 27, 2016, 04:37:21 AM
Sounds like it should probably work fine. A picture might be helpful.

Dan "Doc B." Schmalle
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Offline mike langer

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Reply #2 on: July 01, 2016, 08:21:33 PM
Dan my dmm has a resistance range of:4000M ohm and 40.00 M ohm it also offers 400.0/4000K/400.0K ohm.protection level is 250V DC/Ac RMS.I am getting lots of 0.L MO and random values.the meter is IDEAL 61-312 and i only used to use it to bias a vtl amp.it is self ranging and cannot be set manually.do i need a meter with
higher values?also why term 12 for ground when there is a bunch of stuff connected there-what are other possible locations?like safety ground bolt on chassis?



Offline fullheadofnothing

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Reply #3 on: July 02, 2016, 04:58:50 AM
A lot of decimals got left out of your list, making it hard to make heads or tails out of. The actual ranges in sequence are 400Ω, 4KΩ, 40KΩ, 400KΩ, 4MΩ, 40MΩ.

Are the "lots of OL" readings on terminals marked with an asterisk? Are the ones marked on the list 0 reading 0, and the ones marked with a concrete value reading a value?

Joshua Harris

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Offline mike langer

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Reply #4 on: July 02, 2016, 06:23:46 AM
Good morning,i copied the resistance values directly from the dmm manual-it also has a double asterisk       

that says "accuracy not available for <10n capacitance,
readings on term1=ol mo
2=same
3=same
4=0 0
5=0 0
6=6.28 mo
7=582 mo
8=0
9=6.78/6084 mo
10=5086 mo
This is when i stopped and asked for help-also a variety of random of random numbers showed up in between readings.
thank you you are great    the meter is about 10+ years old  on package it says"ranges:0-400/4k/40k/
400k/4M/and 40M ohm for resistance







Offline fullheadofnothing

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Reply #5 on: July 02, 2016, 07:15:47 AM
When I asked about asterisks, I meant on the resistance list from the Crack manual.

Quote from: From the Crack Manual Resistance Page
The values signified with a * are going to vary from ohmmeter to ohmmeter because these terminals are connected to the filter capacitors, which try to charge themselves off the battery in the meter, causing a fluctuating reading. If the circuit is connected properly these readings will wander in the tens or hundreds of Kohms or higher range. What you want to watch out for is a zero reading at one of these terminals, which would indicate that something is mis-wired.

1 has an asterisk. Reading over limit here is not (necessarily) an issue.
2 has an asterisk. Reading over limit here is not (necessarily) an issue.

3 should be zero. The fact that it is not is very troubling, especially because, as the center terminal of the strip, it is grounded to the chassis. It is also connected via black wires to the ground buss. If you painted your chassis panel, that would be the source of half of this problem. Miswiring your ground wires would be the source of the other half. Not having this terminal properly grounded will cause issues throughout your circuit. Post pictures of your build.

4 has an asterisk. Reading zero here is a sign of a major problem.
5 has an asterisk. Reading zero here is a sign of a major problem.

Terminals 6, 7, 9, and 10 all rely on a solid ground at 3 to function properly. You do not have that, so you need to resolve your issue at 3 to fix these terminals.


Joshua Harris

I Write the Manuals That Make The Whole World Sing
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Offline mike langer

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Reply #6 on: July 03, 2016, 01:13:16 AM
i got a manual mm and am having same problems i sent documentation and pictures ( i'm not sure exactly how to do this)please give good directions on where to start disasembly and start over correcly- i am losing my mind thinking i did a good job-but after 300 solder joints one gets better at it! I will need some solder tabs and other small things that i burned or broke please adviseshould i get some 20ga hook up wire and start over? please advise it seems simple for others to do a terrific job.
Thanks greatly.



Offline fullheadofnothing

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Reply #7 on: July 03, 2016, 05:09:28 AM
Post pictures.

Joshua Harris

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Offline mike langer

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Reply #8 on: July 03, 2016, 10:17:51 PM
Thanks,I have sent 40 or so pictures via gmail and phone, also readings of all terminals (resistance
if i am not clear please call or mail 314 566 9797    [email protected]
your help means a great deal to me thanks mike



Offline fullheadofnothing

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Reply #9 on: July 04, 2016, 06:48:50 AM
I meant post on the forum.

When writing a post, click on the orange text that says "- Attachments and other options". This will bring up a menu for adding pictures to your post.

Joshua Harris

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