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and very rarely ever needs repairs, once you fix them." - Dan/Panther

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Manual: Audacity and dial speed / make-break ratio measurements

Started by dsk, November 01, 2016, 03:54:04 PM

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I have tried to make this manual  and will try to update the manual when I see needs for that. No copyright, but please remember to link to this forum!

If you  need help to read out the data please let us try to help you at this thread.  When you have measured with Audacity, please post you AUP file or link to the file here.

Have fun



Never got any feedback for this one, does that mean that its not easy to read?  If you could help to make it better, thank you!



Yesterday is the 1st time I saw this thread. It looks interesting. I'm interested in giving it a try. Thanks for all the research dsk.


I just measured a "new" dial before cleaning, and maybe I do not have to do anything with it.
As you may see the breaks are slightly uneven but on the other hand my exchange accepts it.


Here is a more rare, and difficult one.  This is obviously not a standard dial, the last break is looooong compared wit the 9 others. They are considerably shorter than a normal break.

As far as I know, this will not be recognized by a normal dial speed meter. Here we may observe it on the visualized recording, and act  as we need.


hey @dsk

Thanks for this manual.
I'm new to this forum and would like to test my dialer with the help of this manual
I have the following question:
The 0.1uf that you suggest, is it an electrolytic capacitor?  if yes, does it matter where its plus leg is connected to?
if not, what kind of cap do you recommend?

On your manual I see you say this adapter is not needed at all. which manual version is the latest?
I recommend you add revision # and date to your manual, jm2c

Will appreciate your reply


I used a non polarized capacitor, but I guess that in most cases you do not have to build that adapter at all, but just connect the dial/telephone to tip and sleeve on the microphone jack. Just remember to short the line before you connect to discharge the ringer capacitor.

The parts and connecting to headphone outlet will make it possible to get a cleaner reading, but by experience; it is rarely needed.



It is a lot tha tmay make the dial test go wrong. The only safe measurment is on a dial disconected from the phone.
On the other hand, it usually is OK to measure on the phone as a complete unit.
Still I hav a German phone that dialde OK om my old exchange, the measurments was insane, both with the digital meter and with the old phone tester. ( BK Precision 1050 ) The dialgizmo did still work :-)
In this case it was the filter across the pulse contacts that made trouble. You may see the details here: