7000DLE MKII (Black Edition) Low Power

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PaulManc
Posts: 49
Joined: Sat Sep 05, 2020 11:08 pm
Location: England

7000DLE MKII (Black Edition) Low Power

Postby PaulManc » Sat Sep 12, 2020 10:22 pm

Whilst waiting for my hardware to build a mic cable to interface PR781 to the MIC input I am trying to do some basic observations.

When the radio arrived 2days it had P1 installed which ran PSDR 3.4.9 no problem. I have had no time to do any tests in its current trim and today I decided to just update everything to get on Thetis (V2.0b firmware & 2.6.9). So im running in Thetis and using the TUNE facility checking the power levels on each band through a CN-801 into a dummy load. The meter is fairly accurate having been compared with an LP100a. Findings below:-

10m=70w, 12m=70w, 15m=45w, 17m=63w, 20m=60w, 40m=69w, 80m=79w, 160m=80watts

A friend of mine has the earlier 7000DLE (Silver) same firmware & thetis and his puts out very close to 100w all bands.

The tune setting is set Power 100 and I have tried Use drive power (on front panel set to 100). Reset the dtb no joy.

Is this common ? Do I need to delve into PA settings :o

Any help gratefully received.
Paul
Manchester
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: 7000DLE MKII (Black Edition) Low Power

Postby w-u-2-o » Sat Sep 12, 2020 11:53 pm

Yes, you need to adjust your PA calibration settings on each band.

Be aware that the drive control is highly non-linear. You can adjust so that a drive setting of 100 equals 100W, or adjust so that you get an accurate result at the drive level required for your amplifier, if you have one. Either way, do not expect drive to equal power except at your selected cal point.
K1LSB
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Joined: Wed Feb 05, 2020 5:25 pm

Re: 7000DLE MKII (Black Edition) Low Power

Postby K1LSB » Sun Sep 13, 2020 3:27 am

Paul,

Yes, you absolutely DO need to "dive into" the PA Gain settings, and you will also probably want to adjust the PA Watt Meter settings. Be aware, the whole process will take some time.

For reference, here are my settings (below). I calibrated my drive into an oscilloscope feeding thru a calibrated 40dB attenuator. After tweaking the PA numbers my power is now within a couple of watts of wherever I care to set my drive, on all of the HF bands (I don't mess with VHF).

NOTE: The settings in the pics are for reference only, your final numbers may be different. Also be aware that small changes to the PA Gain values make a BIG difference.

Mark K1LSB
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PA Settings - Gain.PNG
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PA Settings - Watt Meter.PNG
PA Settings - Watt Meter.PNG (157.33 KiB) Viewed 2487 times
User avatar
PaulManc
Posts: 49
Joined: Sat Sep 05, 2020 11:08 pm
Location: England

Re: 7000DLE MKII (Black Edition) Low Power

Postby PaulManc » Sun Sep 13, 2020 9:58 am

Thank you Gentleman and what a relief too :)

Happy Sunday!
Paul
Manchester

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