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#qlg1 QLG1 RS232 Interface to PC #qlg1

Andrew Lenton
 

Hi Has anyone  directly or indirectly connected a QLG1 into a RS232 PC port and decoded the LAT, LONG, Time ect? if so what interface were you using and what software?

BR

Andrew

Alan G4ZFQ
 

connected a QLG1 into a RS232 PC port and decoded the LAT, LONG, Time ect? if so what interface were you using and what software?
Andrew,

Use a UART or USB/Serial adaptor.
Principle here https://sites.google.com/site/g4zfqradio/u-blox_neo-6-7 goes for any GPS.
U-Center on that page will show any GPS's NMEA, Visual GPS is another.

73 Alan G4ZFQ

KEN G4APB
 

The qlg1 output is TTL, not RS232, so you need to invert the signal and convert the
levels from 0-5 volt switching to -5 and +5v sense. There are simple RS232 chips that can do all this. Then you need an RS232 to USB converter lead (assuming you have no direct RS232 port on your PC.) Then I use a free programme called ‘Putty’ to decode it all. (Windows 7). 

73 Ken G4APB

Andrew Lenton
 

Thank you all for the info and steering me in the right direction, I have a brainbox US101 for an RS232 interface, I will try inverting the 5V TTL output first, as -12 V, is logic 1 in RS232 speak!

73 Andrew

Andrew Lenton
 

found this:

KEN G4APB
 

Looks good Andrew,
interesting use of an inverted electrolytic cap to produce the -ve volts.

73 Ken g4apb 

Alan G4ZFQ
 

interesting use of an inverted electrolytic cap to produce the -ve volts.
Ken,

Thanks, I was not thinking of that.

In fact the circuit is in my opinion far too complex.
All COM port inputs are TTL compatible and the RS232 output can be converted to TTL with a resistor/zener just like the QLG's RXD has.
Assuming Andrew will not be commanding the QLG1 then just an inverter is needed to feed a RS232 port. A transistor and two resistors.

73 Alan G4ZFQ

Alan G4ZFQ
 

A transistor and two resistors.
Like this

73 Alan G4ZFQ

Bob Macklin
 


WHAT AREWE TRYING TO DO???
 
CONNECT A USB/TTL ADAPTER TO A ATMEGA328??
 
The USB/TTL adapter Tx and Rx pins are compatible with the ATmeag Tx and Rx pins.
 
Connect the USB/TTL adapter Tx pin to the ATmega Rx pin.
Connect the USB/TTL adapter Rx pin to the ATmega Tx pin.
 
The Aurdino design uses either the RTS pin (from the adapter) or the DTR pin for a RESET. BUT IT IS CAPCITVLY COUPLED!
 
Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

----- Original Message -----
Sent: Sunday, December 01, 2019 12:42 AM
Subject: Re: [QRPLabs] #qlg1 QLG1 RS232 Interface to PC

The qlg1 output is TTL, not RS232, so you need to invert the signal and convert the
levels from 0-5 volt switching to -5 and +5v sense. There are simple RS232 chips that can do all this. Then you need an RS232 to USB converter lead (assuming you have no direct RS232 port on your PC.) Then I use a free programme called ‘Putty’ to decode it all. (Windows 7). 

73 Ken G4APB

Andrew Lenton
 

Hi all solved made a simple TTL inverter circuit to invert the TTL, so RS232 could decode. also found VisualGPSView softwate.

BR

Andrew