Need help

[Al Goodvibes (14DWT2901)]

Hello everyone, I'm having a power issue, as you can see in the screenshot.
My setup: HL2, RM Italy MLA-300, RF sampler (VK3AMP), ATR-1000 (tuner), EFHW 20m . All my coaxial cables are brand new and from Messi Paolini (Hyper Flex 7).
I'm running Thetis v2.10.3.14x64.
Could anyone help me? Thanks in advance.
73 Dominique.

["Christoph v. Wüllen"]

It seems your feedback level is too high (231, should be about 150).
Use a larger attenuation in the RF sampler (add additional
low-power SMA attenuator at the low-power side)

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[harya sidharta]

Your sampler for 2 k power

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["Christoph v. Wüllen"]

The question is not what power the sampler withstands,
the question is how many dBm come out of it at the
radio's side. A level of about -10 dBm is optimal,
but when properly adjusting the the attenuator/preamp
within the HL2 a large range is possible.

So the problem can only have two reasons:

a) the software did not auto-adjust and move the
preamp all the way down to -12 dB

b) the feedback level is way too high

So my first suggestion is to *measure* how much
feedback comes out of the coupler.

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[Pascal PBY]

Un call peut-être pour répondre en direct ?

[Luca EA8DJR]

Hi Dominique,

I see several things that can cause problems.

Quick attenuate not enabled.

Very high feedback level (must be around 150)

Why you have both vac active?

Why your vac's have all the green and red leds on?

Mic Comp and eq Indicator are at the minimum of the meter

Are you sure to not have CMC flowing in your system (coming from your endfed I.E.)

Your are driving your amp with 1,5W but what is Pout?

Where is your coupler? At the exit of P.A or at the exit of the tuner? From your description i suppose the first option (correct one).

Have you tried with PA in stby? Same results?

Are you sure your atr-1000 can whitstand 300W? It's clearly stated in manual that in some conditions maximum allowed power is well under 1000W ssb ·300w Data/am

Just some options to work with...

Regards

Luca

[Al Goodvibes (14DWT2901)]

Hello Lucas, and thank you for your replies. To keep things simple, I disconnected everything. When I perform a tune with the HL2 alone on a well-tuned antenna without a linkage and with a sampler after the tuner, the results seem similar. See the image... image 1 shows a tune, image 2 shows a linearity test. Do you have any other suggestions?

In any case, thank you for your help. I'm a new HL2 user, and my technical knowledge is generally limited. Best regards.

73 Dominique.

[Luca EA8DJR]

Hi Dominique.

If you works with around 5w you dont need a sampler. The signal for PS is routed internally. And yes pic 1 has problems, but pic 2 shows almost a correct level for PS . 

Make this test: bare bone hl2 connected to antenna, no tuner no sampler. How is swr? how the signal  like pic 2?

I think rf is going into via coax or insufficient shielding.

Make a little period of learning how to stop common mode current and how to protect sdr from interferences using rf chokes and ferrite cores. Use cat6 shielded cable, Better cat 7.

Stay on 5w until you have a nice and clean spectrum and audio on monitor in headphones. Set monitor to 5.

When everything is ok raise pwr to 50w , you will see again the problems, maybe. I have a ferrite ring with the cable turned 3 times on EACH cable (audio, network, power supply, ptt, coax etc) around hl2+ and a Guanella style un-un at the entrance of the coax in the shack. Also end fed are known for causing rf issues.

You continue to show Wattmeter setup, but mor interesting can be PA gain. If you have 100% from 1,8 to 29mhz and, like i see ,you have 2,5 W @0db drive there must be some problem in settings also.

You don't tell if the version of Thetis you use is the one specific for HL2.

Learn all menu screens, better take a picture and print it and make a sort if quick book, very useful.

Your pc is a little overloaded , try to put fps on 25, and 96k of bandwidth for the moment. You will see your cpu usage going down the 59% is showing now.

And, please, if you don't have an Ham call , don't tune in Ham bands. Most of us learned on 27 or as swl. But transmitting is another story.

73 Luca