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Re: Addition power settings?
Posted: Thu Jan 30, 2020 12:17 am
by VK3KYY
I had another thought, that there could be a "user" power setting, where the operator would need to enter the PA drive value into the Options screen for this setting.
However, I think this would probably be too much complication for most people.
And we could add a 5W+ setting which would set the PA drive value to its maximum, but this could potentially overheat the PA FET if people used for a long period.
I would hope that for Ham radio use, people should take responsibility for what power levels they use, but I think a lot of operators are not interested in the technical aspects of the radio and perhaps would not consider the implications of driving the PA beyond its normal limits.
It reminds me of
https://en.wikipedia.org/wiki/Up_to_eleven
Re: Addition power settings?
Posted: Thu Jan 30, 2020 5:11 am
by DU2XXR
50 mW would be useful when very close to the hotspot. but I think retaining 750 mW would still be useful as an increment.
Re: Addition power settings?
Posted: Thu Jan 30, 2020 7:49 am
by IK8JHL
As already explained by Roger, the power increases are not linear and are not the same on all radios, for example I measured the power between 4W and 5W with my rohde schwarz CMT 54, and the power difference is a few mW .. .so I think it is better to have well-differentiated steps eg 50mW, 250mW, 500mW, 1W, 2W, 3W, 5W, 6W
Re: Addition power settings?
Posted: Thu Jan 30, 2020 8:17 am
by F1CXG
An example of power before and after calibration...
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- cal.png (15.07 KiB) Viewed 4155 times
Re: Addition power settings?
Posted: Thu Jan 30, 2020 9:55 am
by VK3KYY
Thanks Thierry
I've looked at the code the calculates the power, between 1W and 5W and also just recalibrated my radio and the power seems more accurate for me.
But I have found a potential problem bug in the code which may make calibrating more difficult, which I have fixed in the firmware which I have attached.
I calibrated on UHF for 439Mhz, and achieved these values
1W = 1.0W
2W = 2.0W
3W = 3.2W
4W = 4.2W
5W = 5.0W
So for me is only the 3W and the 4W which are a little too high.
To calibrate the power.
Set the radio to 1W, then in the CPS adjust the Lower Power value until the radio outputs 1W
Then set the radio to 5W and adjust the High Power value in the CPS until the radio outputs 5W
Note. If after you set to 1W and 5W, turn your radio off and on again to save the current settings.
(Or there is a secret developer button sequence Black + Blue key which saves the current settings immediately)
If everyone's radio behaves like the one I am using for testing, then I can change the code that calculates the 3W and 4W value to slightly lower the value by around 5% those settings.
Re: Addition power settings?
Posted: Thu Jan 30, 2020 12:11 pm
by IK8JHL
OK in the evening i recalibrate all and i can check ( Mu Fuse +1)
Re: Addition power settings?
Posted: Thu Jan 30, 2020 12:46 pm
by IK8JHL
VK3KYY wrote: ↑Thu Jan 30, 2020 9:55 am
Thanks Thierry
I've looked at the code the calculates the power, between 1W and 5W and also just recalibrated my radio and the power seems more accurate for me.
But I have found a potential problem bug in the code which may make calibrating more difficult, which I have fixed in the firmware which I have attached.
I calibrated on UHF for 439Mhz, and achieved these values
1W = 1.0W
2W = 2.0W
3W = 3.2W
4W = 4.2W
5W = 5.0W
So for me is only the 3W and the 4W which are a little too high.
To calibrate the power.
Set the radio to 1W, then in the CPS adjust the Lower Power value until the radio outputs 1W
Then set the radio to 5W and adjust the High Power value in the CPS until the radio outputs 5W
Note. If after you set to 1W and 5W, turn your radio off and on again to save the current settings.
(Or there is a secret developer button sequence Black + Blue key which saves the current settings immediately)
If everyone's radio behaves like the one I am using for testing, then I can change the code that calculates the 3W and 4W value to slightly lower the value by around 5% those settings.
What is the supply voltage you used for calibrations? 7,4 ? or you use battery?
Re: Addition power settings?
Posted: Thu Jan 30, 2020 4:07 pm
by KB8AOB
I would certainly try and probably use a 50 or 100 mW setting as my hotspot now reports RSSI of S9+40 dB at a distance of 10 meters with 250 mW. Plus, I sport a pacemaker-defibrillator so it would make my doc happier.
Re: Addition power settings?
Posted: Thu Jan 30, 2020 6:22 pm
by IK8JHL
This is my value
Re: Addition power settings?
Posted: Thu Jan 30, 2020 8:08 pm
by VK3KYY
IK8JHL wrote: ↑Thu Jan 30, 2020 6:22 pm
This is my value
Thanks.
It looks like the shape of the power curve on everyone’s radios is a bit different.
On UHF, it looks like I need to adjust the parameters to reduce the power a little on the 3 and 4W and possibly lower the 2W a little.
But I would need to see what values other people have