Level Cal adjustment for 7000DLE

w4cm
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Joined: Thu Sep 06, 2018 8:18 pm

Level Cal adjustment for 7000DLE

Postby w4cm » Sun Aug 18, 2019 8:11 pm

Can someone explain the setup under calibration tab for the Level Cal ?
Is there a auto setup using start button ?
Does this set the base noise level of the receiver when terminated ?
If not how do you use the Level Cal to check the 7000DLE ?
Thanks
Cecil/W4CM
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: Level Cal adjustment for 7000DLE

Postby w-u-2-o » Sun Aug 18, 2019 9:53 pm

This changes the power measurement calibration of the radio.

It has to be done using a calibrated signal source.

You attach the signal source to the radio with it programmed to a given frequency and output power level. You tune that signal, then put in the frequency and the level of the calibration signal, then press start.

If you don't have a calibrated signal source you really can't use this feature properly.

I've never heard of anyone who has actually done this finding that their radio was more than 1 or 2dB off from being "perfect". Of course most of those people were using hobby equipment like the Elecraft XG3. Such equipment might very well be off by 1 or 2dB itself, since they are not precision lab instruments and not subject to periodic NIST traceable calibration like a lot of professional lab equipment is.

73,

Scott
w4cm
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Re: Level Cal adjustment for 7000DLE

Postby w4cm » Sun Aug 18, 2019 10:31 pm

Been following the noise measurement discussion on emails. Trying to get the -134dBm level but I think I hit the Cal level start without a ref and changed the setup. I tried a previous saved database and got closer.
How do I start all over and erase the present Thetis 2.6.7 download ?
NC3Z
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Location: Merritt, NC

Re: Level Cal adjustment for 7000DLE

Postby NC3Z » Mon Aug 19, 2019 1:54 am

w-u-2-o wrote:I've never heard of anyone who has actually done this finding that their radio was more than 1 or 2dB off from being "perfect".


I actually calibrate my 7000DLE. I have a R&S SMG 801.0001.43
Gary NC3Z
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w-u-2-o
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Re: Level Cal adjustment for 7000DLE

Postby w-u-2-o » Mon Aug 19, 2019 2:02 pm

w4cm wrote:Been following the noise measurement discussion on emails. Trying to get the -134dBm level but I think I hit the Cal level start without a ref and changed the setup. I tried a previous saved database and got closer.
How do I start all over and erase the present Thetis 2.6.7 download ?

If your saved database is before you did the level cal then you don't need to start over. Otherwise just push the reset database button.
dl4zbg
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Joined: Sun Apr 09, 2017 5:33 pm

Re: Level Cal adjustment for 7000DLE

Postby dl4zbg » Fri Oct 18, 2019 12:57 pm

Last weekend I successflly moved from P1 to P2 (Thetis 2.6.8 c5) with my 7000 DLE. Checking my S- meter readings with my XG3 I noticed that they were 8 dB too low. So I tried to perform a level calibration on 30m like I did "in the old world" (P1) with PSDRmRX. But I was only able to change the frequency in 1 MHz Steps and the level in 10dB steps. This was different with PSDRmRX.

My question: is this not possible (frequency in kHz and level in single dBm) or did I overlook something?

Thanks

Volker

DL4ZBG
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w-u-2-o
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Re: Level Cal adjustment for 7000DLE

Postby w-u-2-o » Fri Oct 18, 2019 1:33 pm

The spinners do only move in those increments, but you can type the exact value that you want into the box. I just level calibrated my setup using a NanoVNA and some attenuators to put it at exactly -73dBm. Mine was reporting -79 before calibration.
dl4zbg
Posts: 48
Joined: Sun Apr 09, 2017 5:33 pm

Re: Level Cal adjustment for 7000DLE

Postby dl4zbg » Fri Oct 18, 2019 5:17 pm

I tried this of course. Yesterday I was not able to edit these values. The edit window background became blue.....
Restarting Thetis 2day and it worked this time. Now the S- meter readings are correct.

Very funny.

TNX

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