Re: Qgl1 gps question


Roger Hill
 

Hi Art.


So it sounds as though you have a faulty IC2 (unlikely), or a short to ground on the output side (pin 2).


You can check the short by removing power from the unit, and with your meter on 'Ohms', check from pin2 to ground...it should be a very high value. A low value will cause the symptoms you are seeing.


Possibly C4 is in backwards.

Roger

8P6RX

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Roger Hill
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On 2021-02-06 10:51, Art Olson wrote:

Eike

Think I have located the problem - no 3.3v on the pin 2 of IC2. When powered up IC2 run hot to the touch.  There is 5.1 v on pin 3 (vin). Verified R7 and R6 are correct values. I have looked for a pinout diagram for the Rf module but could not locate one so don't know the pin numbering on the module. But would seem without any 3.3v from IC2 it wont work. there is 3.3v when powered off on, I assume pin 22 of the RF module

Art
N2AJO

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