Jim, There is another place you may be missing and I will have to find it later and let you know. But the code does this by calling a SPI write routine to the AX device and in this routine the value is truncated down to 0xff.  However when I tested other values like 0xe0 the thing just stopped transmitting.

I can copy the signal in my lab with 0x0d. Maybe it is increasing power someplace else but I hope not so we can get some more bang.

I plane to ship you a board tomorrow. I thought I was going to get it out today but I kept finding issues on the board I had to fix. This board still has a bit of week power source. The 5V supply is running about 4.75 and the 3.3 is a little low like 3.25. May need the additional headroom from 5V. There is a resistor string on the back of the board that programs the level. 

I noticed today that the board did not come up when I powered it and then I removed power and reconnected and that time it worked fine.


The board needs a bit more voltage feeding the preamp on the RX input to get more gain. It is operating with 30 mA and would like to have 60 mA to have full gain. The 3.3V minder chip I thought was set for enough current to feed everything but may need to move the monitor resistor up to allow a full 600 mA.

I did not see these issues on a board I just sent to Chris.

I am ready to share the fun though and instead of continuing to debug and chase problems I am going to send you a setup tomorrow. I may poke at it a little in the morning but not much.

At this point when the board powers up it does transmit and it will receive or at least it will get the rf to the AX5043 inputs. I can see it there.

Your call is programmed into the flash so play with it until you get a programmer.

I will send you a programmer later. Burns is sending me two and soon as I see them and add a connector I will push one on to you.

Bob
From: Jim McCullers via pacsat-dev <pacsat-dev@amsat.org>
Sent: Tuesday, February 20, 2024 8:24 PM
To: 'Pacsat Dev' <pacsat-dev@amsat.org>
Subject: [pacsat-dev] PacSatSW - Transmitter Power Level
 

Bob,

 

Looking at the lastest code I see two places, which is one to many, where the transmit power level is set.

They are:

 

ax5043-ax25.c            Lines 435-436

 

TxTask.c                     Line 63                        calls radio_set_power() at line 112

 

They both set the power level to 0x0020 which is very weak.

 

I don’t see a place that sets the transmit level to 0x0d.

Let me know where you found that reference.

 

I would suggest setting both places to 0x0FFF for maximum output (+15 dbm)

 

Jim McCullers

WA4CWI