Search found 81 matches

by AB2EZ
Sun Apr 01, 2018 7:41 pm
Forum: Digital Mode & Logging Software
Topic: Amplitude modulation on 'constant envelope' modes
Replies: 19
Views: 580

Re: Amplitude modulation on 'constant envelope' modes

Conrad

Hi!

Any update? E.g power out v. FT8 tune frequency?

Stu
by AB2EZ
Mon Mar 26, 2018 6:45 pm
Forum: Digital Mode & Logging Software
Topic: Amplitude modulation on 'constant envelope' modes
Replies: 19
Views: 580

Re: Amplitude modulation on 'constant envelope' modes

Conrad If you change the WSJT-X FT8 tune frequency in 500Hz steps... between 500Hz and 2500Hz... what are the corresponding output power readings... relative to the 500Hz reading? Also, have you tried toggling the transmit equalization on and off to see if the transmit equalizer is “stuck” in the ac...
by AB2EZ
Sun Mar 25, 2018 5:40 pm
Forum: Digital Mode & Logging Software
Topic: Amplitude modulation on 'constant envelope' modes
Replies: 19
Views: 580

Re: Amplitude modulation on 'constant envelope' modes

Conrad Since A) You see no amplude modulation when using WSJT in tune mode ... with a given nominal frequency (e.g. 500 Hz)... but you see a variation in the RF output when you change the nominal frequency. B) You have looked directly at the audio output of your sound card (digital audio interface),...
by AB2EZ
Sat Feb 24, 2018 5:36 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Rob Yes... doing this measurement with an auxiliary receiver in the same location as one's transceiver/amplifier is much more complicated than it appeared to be when we first thought about it. Even with the relatively low internal crosstalk levels in the more recent ANAN-XXX products, I remain skept...
by AB2EZ
Tue Feb 20, 2018 7:53 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Rob I think your latest posted measurement results are very helpful, but: You wrote "The third-order IMD results were not as good as seen when running the transmitter into the dummy load where the signal strength into the receiver ranged between 20dB to 30dB over S-9. I think I would agree with...
by AB2EZ
Tue Feb 20, 2018 7:32 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Gary

You appear to have misunderstood my recent post. Please read it again.

Stu
by AB2EZ
Tue Feb 20, 2018 5:32 am
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Rob Scott Thinking about this some more.... The power leaving the transceiver is only around 13dB less than the power leaving the external amplifier. With a dummy load attached to the external amplifier (and with the amplifier input being equivalent to a dummy load at the output of the transceiver)....
by AB2EZ
Mon Feb 19, 2018 9:46 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Scott
Rob

Assuming that the software being employed with the RSP1 allows one to increase the averaging time... shouldn't one be able to significantly reduce the effect of phase noise in the panadapter display produced in the 2-tone test by increasing the averaging time to a much larger value?

Stu
by AB2EZ
Mon Feb 19, 2018 6:58 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Rob The 2-tone spectrum looks reasonably clean on the RSP1 display... but it is difficult to confirm that the IMD products are more than 40dB below the principal tones. I.e. -53dm - (-93dBm). On the SSB displays... its appears (with some interpretation to ignore the 2nd peak on the RSP1 display) tha...
by AB2EZ
Sun Feb 18, 2018 7:19 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

Rob I'm thinking of buying an RSP1A from HRO If you are transmitting with your ANAN + external AMP... and also using your RSP1 for monitoring your amplifier's RF output spectrum... How do the 2-tone spectrum readings of IP3 compare (ANAN DUP vs. RSP1) when you have a) Pure Signal turned off b) Pure ...
by AB2EZ
Sat Feb 17, 2018 6:06 pm
Forum: PureSignal Operations
Topic: Accuracy re fidelity on/with the TX display while using PS
Replies: 33
Views: 1422

Re: Accuracy re fidelity on/with the TX display while using PS

One of the things that could cause a disparity between the DUP display and the actual RF output spectrum of the amplifier is non-linearity being introduced by the the coupler. I.e. if the output of the coupler's sampling port is not linearly proportional to the RF output of the amplifier* Therefore,...
by AB2EZ
Thu Feb 15, 2018 5:38 pm
Forum: PowerSDR mRX
Topic: Transmit signal levels on panadapter
Replies: 19
Views: 845

Re: Panadapter & waterfall settings

Gary

Don't forget to check the SMA jumper cables between the coupler, attenuator(s) and the radio for: connector=>connector center conductor and ground DC connectivity, and no shorts between center conductor and ground.

Stu
by AB2EZ
Wed Feb 14, 2018 12:56 am
Forum: PureSignal Operations
Topic: Panadapter "view" in TX with DUP on - using PS
Replies: 7
Views: 380

Re: Panadapter "view" in TX with DUP on - using PS

Gary It is also possible that the sample of the RF being produced by the Xtronics XDC-4SO coupler is a distorted (non-linear) sample of the RF. There are a number of things that could cause this. For example, the coupler contains ferrite-core transformers. If one of the cores has been damaged by ove...
by AB2EZ
Tue Feb 13, 2018 8:24 pm
Forum: PureSignal Operations
Topic: Panadapter "view" in TX with DUP on - using PS
Replies: 7
Views: 380

Re: Panadapter "view" in TX with DUP on - using PS

Adding to my post (above) ... it is my understanding that some ANAN 8000 owners have reported an assembly error... in which the two internal Pure Signal cables that attach to the Pure Signal in and Pure Signal out connectors on the rear of the transceiver are swapped.

Stu
by AB2EZ
Tue Feb 13, 2018 6:29 pm
Forum: PureSignal Operations
Topic: Panadapter "view" in TX with DUP on - using PS
Replies: 7
Views: 380

Re: Panadapter "view" in TX with DUP on - using PS

Gary When transmitting... with DUP active.... the panadapter displays the spectrum of the total signal arriving at the input to RX1. This consists of the sum of two RF voltages: a(t): The sample of the amplfier's RF output that is being fed into RX1 from the coupler at the output of the amplifier b(...
by AB2EZ
Fri Feb 02, 2018 6:28 pm
Forum: PowerSDR mRX
Topic: Feature interaction between monitor and AM
Replies: 11
Views: 586

Re: Feature interaction between monitor and AM

Scott Good suggestions! I had never used the ALC Comp meter reading... but I have now switched to that... and turned up the microphone gain to obtain about 1dB on peaks. I was curious about the changing output level behavior of the MON functionality (as explained by Warren)... and I am still curious...
by AB2EZ
Thu Feb 01, 2018 5:43 pm
Forum: PowerSDR mRX
Topic: Feature interaction between monitor and AM
Replies: 11
Views: 586

Re: Feature interaction between monitor and AM

Warren Thanks for the detailed explanation of why the level of the monitor audio output can change each time PureSignal recalibrates. Do you have any idea (perhaps speculative) as to why PureSignal would occasionally stop applying a correction... immediately after the green calibration light flashes...
by AB2EZ
Thu Feb 01, 2018 12:29 am
Forum: PowerSDR mRX
Topic: Feature interaction between monitor and AM
Replies: 11
Views: 586

Re: Feature interaction between monitor and AM

Rob Scott I agree with Rob that the interaction I described in my original post involves the combination of PureSignal, MON, and AM operation. Additional observations 1. The sudden drops and sudden restorations of the monitor volume occur at instants in which PureSignal is undergoing a re-calibratio...
by AB2EZ
Wed Jan 31, 2018 4:29 am
Forum: PowerSDR mRX
Topic: Feature interaction between monitor and AM
Replies: 11
Views: 586

Re: Feature interaction between monitor and AM

Scott

My 10E has been modified properly for Pure Signal operation with my external linear amplifier.

The feedback level is correct

Stu
by AB2EZ
Tue Jan 30, 2018 10:16 pm
Forum: PowerSDR mRX
Topic: Feature interaction between monitor and AM
Replies: 11
Views: 586

Feature interaction between monitor and AM

Normally I use an RF sampler + peak detector to monitor the modulation of my AM output signal. For SSB I use the HPSDR "monitor" functionality. Today, for the first time, I used the HPSDR monitor function to listen to the modulation of my AM output signal. I noticed the following: After ab...
by AB2EZ
Fri Jan 12, 2018 2:08 pm
Forum: PowerSDR mRX
Topic: CW Mode Operation
Replies: 34
Views: 1794

Re: CW Mode Operation

Prem In CW mode, the radio (if operating as designed) will only switch to transmit (MOX button illuminated) if the dot or dash key contact is closed (or if both are closed simultaneously. In iambic mode ... closing both the key contacts simultaneously will produce an output which is an alternating p...
by AB2EZ
Thu Jan 11, 2018 7:35 pm
Forum: PowerSDR mRX
Topic: CW Mode Operation
Replies: 34
Views: 1794

Re: CW Mode Operation

Prem The data sheet for U25 is readily available on-line. The truth table is included in the data sheets. With both the dot and dash inputs in key up position (I.e. Not shorted to ground, and therefore both measuring 3.3V to ground), the dot and dash output pins should also bothmeasure 3.3V to groun...
by AB2EZ
Thu Dec 28, 2017 3:56 pm
Forum: Digital ("Virtual") Audio
Topic: VAC SIGNAL NOT STEADY
Replies: 31
Views: 3210

Re: VAC SIGNAL NOT STEADY

All VAC1 + FT8 has been working flawlessly (no glitches on the waterfall, etc) for about 1 month now. I have installed the last several HPSDR updates without any problems. As I cycle through various bands and band segments... VAC1 automatically turns on or off... depending upon how I have set it for...
by AB2EZ
Fri Dec 22, 2017 3:43 pm
Forum: PowerSDR mRX
Topic: PowerSDR mRX PS 3.4.7 Released
Replies: 10
Views: 965

Re: PowerSDR mRX PS 3.4.7 Released

Doug

Thank you for the new release! In particular, thank you for the separate receive and transmit waterfall level settings.

Happy Holidays
Stu
AB2EZ

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