Re: No output QCX 40 output drains show 1.6 watts in receive


George Korper
 

D!1 at output is 3.3 and IC1 pin 1 is  1.8 assuming that is top right pin.


On Wed, Dec 11, 2019 at 12:33 PM George Korper via Groups.Io <georgekorper=gmail.com@groups.io> wrote:
Alan,
The drain and gate on Q1 Q2 and Q3 are 5 v and the source 0. CLK 1 goes from 1.7 on receive to zero on transmit.
Not sure of pinout on IC1 directly. 
George






On Wed, Dec 11, 2019, 3:54 AM Alan G4ZFQ <alan4alan@...> wrote:
> In transmit nothing on the IC3 changes.

George,

IC3 looks as if it has failed. If pins 1,2 are high then pin 1 should be
low.
What are the voltages on Q1,2,3?

Also it looks as if IC1 is not sending a TX signal to IC3 and that Clk2
is not turned on for TX.
Is it going into TX mode? Does IC1 pin 3 go low when the "Key" switch is
pressed?

73 Alan G4ZFQ


>     IC3 Voltages LCD unplugged:
>     some values rounded off.
>     1) 5
>     2) 5
>     3) 5
>     4) .02
>     5) .01
>     6) 5
>     7) 0
>     8) 5
>     9) 0
>     10) 0
>       11) 0
>     12) 5
>     13) 5
>     14) 5
>




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