Re: Status: IC-7000 Audio Levels for V/UHF and HF modes #draws #hfmodes #ic7000


Jack Spitznagel
 

Basil,

Found what I thought I remembered about IC-7000 data port sensitivity in the
SignaLink FAQ at www.tigertronics.com. Obviously this will have an impact on
DRAWS setup and operation with the IC-746Pro and the FT-450 as well.
Naturally, older radios will get pressed into field service - these just
happen to be commonly available and are "shelf spares" in quite a few
shacks. I am going to see if I can find more about the solutions to this
problem:

"ATTENTION IC-7000, IC-746PRO and FT-450 Users - Some customers have
reported that these radios have unusually sensitive Data Ports, which can
make adjustment of the SignaLink's TX knob somewhat difficult. If this is
the case with your radio, then *you should find that the procedure above
where you install jumper JP4 and lower the Wave volume control resolves the
issue*. However, you may also need to turn the radio's RF Power menu
setting down for better control. A power setting of 35 to 45 watts usually
works well for 25 to 35 watts of actual RF output as measured on a watt
meter, or the radios Power Output meter. "

Jack - KD4IZ

-----Original Message-----
From: udrc@nw-digital-radio.groups.io <udrc@nw-digital-radio.groups.io> On
Behalf Of Basil Gunn
Sent: Sunday, December 23, 2018 17:58
To: udrc@nw-digital-radio.groups.io
Subject: Re: [udrc] Status: IC-7000 Audio Levels for V/UHF and HF modes
#draws #ic7000 #hfmodes


First of all, thanks for all the time you are putting in.
See suggestion for PCM, LO Drive gain below.

Tried to take a scientific/stepwise approach with setting the DRAWS
board audio out today.

I went through the entire level and deviation check routine again
today and wound up with very similar settings to my previous attempts.
I then tested direwolf VHF-FM first and then after disabling AX25,
fldigi and wsjt-x on HF. Results "ain't purty", but at least everything
is being consistent.

Software function status:

VHF - with direwolf/Xastir transmitting and receiving on the local
packet network does work .

Comment: I don't really have a an easy/better way to test than
function on APRS network locally. I have a sense that the audio may be
high, but I won't know until I have time to putter with Spectrum Lab.
It will become my "Deviation Meter" with an IC-7100 functioning as my
"sensor".

Check this out by John Ackermann N8UR
Look for: "The No-Test-Equipment Packet Adjustment System"
https://www.febo.com/packet/layer-one/transmit.html

Do you have a handy talky?
use the measure_deviate script: n7nix/deviation/measure_deviate.sh
Pick a tone, bring-up alsamixer Set PCM to 0db & drop LO Drive until there
is no clipping ie. no distortion or just follow John Ackermann's suggestion.

UHF - have not tried anything yet. TBD

HF - With the alsamixer settings below (visually they produce the
"lowest splatter" per an IC-7300 panscope and using Spectrum Lab 2
with the IC-7300 internal audio subsystem via USB. Rig coax is
grounded, RF gain at 20% with 20dB of attenuation:

1. Fldigi drives the IC-7000 up to full power (if set) but transmits a
very dirty sig at any power above 5%.

Comment: The sig can be copied by others, but the ALC bar is reading 60%.
Not making any friends in the PSK world. These are ALC symptoms.
Reducing either the PCM level or LO Driver Gain results in very much
increased noise and a feedback like whistle at a different freq.
Increasing the two settings results in more splatter and harmonics.

2. WSJT-x receives just fine but DRAWS produces only an extremely low
transmit audio level according to the IC-7000 and signal being
received on other transceivers. Only testing with FT8 no other JT modes
tested. TBD:
wspr.

Comment: In transmit there is no Power Out deflection on the IC-7000 -
even if I adjust the PCM and IO Driver levels to the max, together or
separate.
So the PCM/LO Driver Gain level settings that "work" in fldigi, don't
work in wsjt-x. I even went back to check that invoking wsjt-x did not
somehow tweak the alsamixer settings. they remained the same.

Key Question: Why is DRAWS overdriving in fldigi, and then not putting
out enough audio level to drive the IC-7000 to set power level in
wjst-x FT8 mode with alsamixer settings remaining the same between apps?
I don't have an answer but your description is a good data point.

Here are my current alsamixer settings:

PCM L:[-21.50dB], R:[-21.50dB

ADC Level L:[-2.00dB], R:[-2.00dB]

LO Driver Gain L:[6.00dB], R:[6.00dB]

IN1 L:[10kOhm], R:[10kOhm]

IN2 L:[Off], R:[Off]
So PCM set that low is very suspicious. It means you are not using many
bits of the CODEC. I would play with returning PCM at least close to zero &
dropping LO Driver Gain down.

I am stuck until I can figure out how to coerce wsjt-x into
transmitting at set power with the same audio input levels to the rig as
provided in fldigi.
At this point I don't even care if the overdrive issue isn't solved. I
have decided to put the FT-817 aside because other are
working/reporting on it. I am only testing with the Beta 5 provided
software and the IC-7000 until I get these critical pieces working
reliably because that will be my main radio for this DRAWS kit.

Now need to go pay attention to other stuff (like family and the local
zoo of 4-legged furries we keep here on the farm).
Yep. I understand.

Thanks for thinking this through with me.
Thanks for taking such a methodical approach.

KD4IZ

Jack Spitznagel






--
J Spitznagel
Science River LLC
KD4IZ

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