Author Topic: Help with setting up Grandstream HT502  (Read 1436 times)

Offline shadow67

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Re: Help with setting up Grandstream HT502
« Reply #15 on: May 14, 2017, 07:48:04 PM »
Thank you for those replies. I am not sure but I can try to record some 0s

Offline Jack Ryan

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Re: Help with setting up Grandstream HT502
« Reply #16 on: May 14, 2017, 08:23:00 PM »
It's to do with the make/break ratio of the dial. Here in the UK we have a lot if trouble with this becausebthe ratio is different to the US and the Grandstream 502 is set to wirk with US phones.

I've never had a problem with the make-break ratio when using phones from different parts of the world (except the IWE "long last pulse" dial).

The ATA is somewhat sensitive to dial speed and very sensitive to bounce or noise caused by dirty contacts.


Offline andy1702

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Re: Help with setting up Grandstream HT502
« Reply #17 on: May 15, 2017, 06:08:10 PM »
I think it's a combination of dial speed and make/break the ATA is sensitive to. In general a slow dial seems to cause more problems than a fast dial, unless it's ridiculously fast. I use the old GPO cheat to set dial speeds. Dial a 0 and as you let go count out loud at a normal speed "one onethousand and one." You should finish speaking just at the moment the dial reaches the normal position. As for the make/break, I just bend the pulse contacts until they barely open. You shoukd just be able to see they've parted but not much more.

To be honest I've never needed to do the speed test with Audacity thing. Just setting by eye etc as above has woeked for me with every phone I have. This is for adjusting UK phones to work with the Grandstream 502 though, so may be different in the US. I do have a few American phones, but these all worked ok when they arrived without any adjustment (mainly 500s).

The adjustments I make to the 700s, trimphones, bakelite phones etc are very small, but they do makenthe diffwrence between success and failure when making a call.

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