[Resolved - Speaker mic cable touching the antenna] PTT Latch Question

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vk2fmet
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[Resolved - Speaker mic cable touching the antenna] PTT Latch Question

Post by vk2fmet » Tue Sep 15, 2020 11:51 pm

I've been using the PTT latch feature for a while with a speaker mic. I have a friend who also uses it in this config.
There was always what appeared to be an issue using this feature against my local repeater.. it doesn't latch up - instead it lets go pretty much straight away. So I turn latch off when working the repeater.

This didn't happen against the hotspot... it's worked well.
But since the latest stable there seems to be a random un-keying i.e. it keys up but lets go after a few seconds. (similar to how it behaves previously against a repeater).

So my questions are, what should I be expecting in the use of the PTT latch? Is there a subtlety or other config I should be aware of? I use timeout as described in the docs.
I've tried a longer key-up before I let go (various lengths of time) with no difference in the behaviour of letting go.

We both have different speaker mic hardware but the same behaviour

Alan

VK3KYY
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Re: PTT Latch Question

Post by VK3KYY » Tue Sep 15, 2020 11:58 pm

I don't use this feature, but there was a bug where pressing SK2 when transmitting to send the 1750Hz Tone "burst" caused the PTT latch to drop

This got fixed a few weeks ago and will be in the Stable and Development releases

Not sure about random de-keying.

Though some very old radios are known to have problems where they seem to get random key presses to the keypad, possibly due to RF induction.
Newer radios don't have this problem (new in the last year to 18 months or perhaps last 2 years)

vk2fmet
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Re: PTT Latch Question

Post by vk2fmet » Wed Sep 16, 2020 4:43 am

OK - well I assume you mean old GD-77s? The ones I refer to are less then 6 months old
I've never used the tone burst feature

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F1RMB
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Re: PTT Latch Question

Post by F1RMB » Wed Sep 16, 2020 5:14 am

Hi,

Do you use the same power output when hotspot and repeaters ?
What is happening when using your GD without external mic, does it de-key ? At the first glance, it looks like similar issue when using GD as hotspot (back RF).


Cheers.
---
Daniel
73 de Daniel.

vk2fmet
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Re: PTT Latch Question

Post by vk2fmet » Thu Sep 24, 2020 3:07 am

I use 50mW on my hotspot.
I typically use as little as possible against the local repeater but I have used the full range in testing.

With or without external mic, the latch feature is the same i.e. unreliable. It is slightly more reliable on the hotspot. It is quite unreliable on the repeater.

I have turned it off since the last firmware update because it is too unreliable now.

pity - it's a nice feature - keeps the pressure point off the thumb - I was liking it a lot.
Alan

vk2fmet
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Re: PTT Latch Question - solved

Post by vk2fmet » Thu Sep 24, 2020 5:49 am

ah - ha!
Found it...
It's the cable coming up from the speaker mic.. if it comes close (within about 4mm) and certainly if it touches the antenna, bang - the latch lets go.
issue solved.
The kenwood plug makes the cable exit up so I'll tie the cable over, return it.
Alan

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F1RMB
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Re: PTT Latch Question

Post by F1RMB » Thu Sep 24, 2020 6:00 am

;)


Cheers.
---
Daniel
73 de Daniel.

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