DDS/Front panel voltage table

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DDS/Front panel voltage table

Postby NQ3RP » 24 Jan 2019 13:35

Looking for help on my TRX2A problem. My radio turns on with a push of power button, long push does nothing. Will not turn off with power button. When it turns on I have no backlight and only blocks on first row of display very dim. I checked the voltages on the display pins -2 = 5V,15 = 12V and 16 = 10V. I'm trying to troubleshoot the front panel but don't have a voltage table so no idea of what to look for. The brightness and contrast circuits I've ohmed and looks good but need a voltage reading table. What other voltages should I check? I expect the DDS is working because the power button works, is that correct? Any help appreciated.

John
NQ3RP
NQ3RP
 
Posts: 15
Joined: 11 Dec 2017 20:56
Location: USA

Re: DDS/Front panel voltage table

Postby NQ3RP » 04 Feb 2019 23:03

Just to document and keep everyone informed of my TRX2A build here's the update. I destroyed the first DDS by improper soldering of the dsPIC. The second I sent to a builder who did a beautiful job but by using improper grounding technique and improper voltage jumpers I destroyed that one. It would boot but the display was locked in blocks so it never would display with the dsPIC holding 5V on the R/W pin. So on to the last one. After all I've learned, practiced soldering QFP100 chips, and some meditation I will build the last one. If I fail then I will move on to other projects. Thanks for your time reading my predicament and especially thanks to Adrian for his help.

John
NQ3RP
NQ3RP
 
Posts: 15
Joined: 11 Dec 2017 20:56
Location: USA


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