Tristar 777 Nato Beep ?

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littledot
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Tristar 777 Nato Beep ?

Post by littledot » Friday 23rd Sep 2011, 7:08

Can anyone out there shed any light on what parts/wires need to be swapped/replaced on the PTZZ080AOX board in the Tristar 777 to get the Nato 2000/Hygain 8795 type beep.

I have searched high and low and looked at various diagrams but they are either too unreadable or are not the exact diagram so the beep portion is left out.

TIA
S7001947.JPG
The PTZZ080AOX as it is in the Tristar 777
S7001947.JPG (101.97 KiB) Viewed 4817 times

zodiac
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Re: Tristar 777 Nato Beep ?

Post by zodiac » Friday 23rd Sep 2011, 12:03

The 777 doesn't have a beep fitted as standard like the Nato, you'll have to fit one.
How far is it.
Twice it's length from halfway.

littledot
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Re: Tristar 777 Nato Beep ?

Post by littledot » Friday 23rd Sep 2011, 21:31

The PTZZ080AOX in the Tristar 777 & Superstar 2000 can be "rearranged" slightly to get the same beep as the nato 2000 and hygain 8795, I just need to know what and where, The Hygain 8795 PTZZ080AOX diagram you can make out the slight changes but is not clear enough.

Someone out there must have done it before.

Cheers

littledot
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Re: Tristar 777 Nato Beep ?

Post by littledot » Saturday 24th Sep 2011, 0:39

Well I managed too suss it.

For anyone thats interested

For the Tristar 777

On the PTZZ080AOX

Remove the wire that jumps from [9] to the cathode of D4

Add a 1N4148 diode in D4

Remove D3

Remove the one end of R13 [The end closest to D3] and connect the free end of R13 to ground.

Remove the pin marked [1] [this is the constant voltage from the mode switch when on CW]

The now free hole [1] connect this to a constant voltage of around 8v

Remove the pin marked [4] next to the relay [this comes from the TX pin on the mic socket]

Connect that wire [usually purple] to the pin marked [P] Theres already a pin in the hole [P] which goes to the CW socket, Leave this in place.

Remove the wire from the hole marked [6] and put this in the now vacant hole [4]

Thats it you should now have a Nato 2000/Hygain 8795 beep, The duration of the beep is a little longer than normal but changing the value of C1 22uf to a 10uf was about the best.

This should also work in the Superstar 2000

zodiac
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Re: Tristar 777 Nato Beep ?

Post by zodiac » Saturday 24th Sep 2011, 11:06

Well we learn something new every day, and you've explained it so well.
Thank you.
How far is it.
Twice it's length from halfway.

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