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 Icom 7300 SSB average power mod 
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Post Icom 7300 SSB average power mod
It's very similar to the one doing the rounds for the 7100.
Has anybody done this yet, reports please.

http://sp3rnz.blogspot.co.uk/2017/01/icom-ic-7300-ssb-power-mod.html

Cheers

Alan

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Thu Apr 27, 2017 7:19 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Neither of mine give a low output like described.

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Thu Apr 27, 2017 7:51 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Sangoma wrote:
Neither of mine give a low output like described.


Mine seems OK as well, perhaps the ones they were testing had the early release firmware.

I'm not going to bother as it drives the amp OK.

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Thu Apr 27, 2017 8:34 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
M0XAL wrote:
Sangoma wrote:
Neither of mine give a low output like described.


Mine seems OK as well, perhaps the ones they were testing had the early release firmware.

I'm not going to bother as it drives the amp OK.


Maybe they expect the meter to hover round 100W on SSB, a 30W average power would be about normal anyway with no processing.

Yes, If I use an amp, it needs 6-7W for 400W out, which would be ideal if I wanted to use it.

I wasn't particularly struck by the article :)

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Thu Apr 27, 2017 8:50 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
I wonder if they have tried something simple like taking out the fuses and brushing them up with a fine abrasive? The IC-7000 used to loose power out put due to oxidation on the pins of the fuses, since they both use the same holders.

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Thu Apr 27, 2017 10:12 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Some Polish Ham thinks he knows better than the Icom factory.
Nothing new, people were complaining about the same thing from the TS 480HX, I happen to own both and don't think there is any issue with average talk power.
There will always be messers who think they know better.

Just hope I don't come across one that lives near me.

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Thu Apr 27, 2017 12:13 pm
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Its almost like people measuring SSB power saying its low don't use proper peak hold meters and that they also don't know how much compression they should have or how much ALC they should be running. 20dB is not it and there should be NOTHING AT ALL showing on the ALC meter other than the odd tickle on voice peaks.

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Fri May 05, 2017 5:40 pm
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
I've just come across this thread.

At 50% mike gain and 6dB compression my 7300 gives a healthy 100W on peaks.

Never had an issue.

I think Icom knows how to design an HF transmitter by now!


Sun May 21, 2017 3:59 pm
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
G0UOO wrote:
I've just come across this thread.

At 50% mike gain
!


:shock:

Bet the ALC meter is doing a hell of a merry dance. My mic gain on my Icom 7300 is at 9%. Yes, nine percent and I get 100W on peaks. On the Icom 7000 I had I used to run 18%. In fact on all my videos I've done you'll not see the mic gain higher than 1/3 and that is for a FT950, FT1000MP MKV Field, a Kenwood TS590S and a couple of Kenwood TS480s.

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Sat Jun 03, 2017 8:27 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
M0GVZ wrote:
G0UOO wrote:
I've just come across this thread.

At 50% mike gain
!


:shock:

Bet the ALC meter is doing a hell of a merry dance. My mic gain on my Icom 7300 is at 9%. Yes, nine percent and I get 100W on peaks. On the Icom 7000 I had I used to run 18%. In fact on all my videos I've done you'll not see the mic gain higher than 1/3 and that is for a FT950, FT1000MP MKV Field, a Kenwood TS590S and a couple of Kenwood TS480s.


Is that the stock hand mic came with it?

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Sat Jun 03, 2017 9:00 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Hi All,

The ALC meter pops up to around 30 to 50% of full scale on peaks, and the "Comp" meter peaks around 10dB. This is with the standard mike about 2" from my mouth and talking in a normal tone - I don't "talk it up". It pretty much follows what's in the operating instructions.

Winding the mike gain from low to high doesn't seem to do much apart from make the audio sound louder, picking up some room noise at the high end. The RF output seems clean regardless.

What does the mike gain actually do in these DSP radios? Providing you don't overload the input to the ADC it's all number crunching in software. Surely that's written to prevent what we might call "overdrive" in an analogue transmitter, and the output from the DAC towards the PA can't go higher than a given voltage for all 1s input. I don't know. I'm only trying to think it through as a layman in these things.

Rob.


Mon Jun 05, 2017 8:04 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Having read a bit about this now, it seems that the ALC action in an SDR is a very different thing to that in an analogue design.

In an SDR the RF drive applied to the PA is set not to exceed a certain level. The output of the DAC will not exceed this level, and there is no ALC at this point. The ALC in an SDR radio is actually applied at the AF input to the ADC to prevent clipping occuring due to excessive level. The ALC meter is showing the control applied by the ALC algorithm at the ADC. If this runs out of range "overdrive" will result in signal distortion, but it's NOT RF distortion from overdriving the PA. That's why winding the mike gain up and down doesn't distort the RF output.

Am I on the right track?


Mon Jun 05, 2017 8:56 am
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
Anyone?


Wed Jun 07, 2017 3:02 pm
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
437 views and no further comment!

I thought this was a technical hobby.


Sat Jun 10, 2017 12:59 pm
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 Icom 7300 SSB average power mod 
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Post Re: Icom 7300 SSB average power mod
I am no expert on SDR technology, however I am currently building my own SSB transceiver, dual-conversion superhet design however I have some experience with DAC's as the VFO is uses an AD9959 DDS with four independent output channels with amplitude control, I have implemented a simple solution for providing a constant output over the entire tuning range of +7dBM for the first mixer by way of setting the DAC amplitude register for each band. So I would think that in the case of the 7300 that the audio from the mic amp gain control does increase the amplitude albeit with some ALC control on the audio itself, not seen the 7300 schematic so just best guessing here, however if the DAC amplitude register range is 0-1023 and has a max upper limit set then the output amplitude should not go above that level.


Sat Jun 10, 2017 1:10 pm
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