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ic706mk2g on AM

davegrantsr

Active Member
Oct 30, 2005
593
89
38
saw a post on qrz today that got me thinking. tried mine on AM & got the same results he did-'so-so' at best on AM. anybody use one here on AM? how does it perform there? did you do anything to MAKE it perform well?
 

I only used AM when I had it in the big truck.

On Sesame Street, so I never asked for an audio report, figured I'd find out I needed echo.

I guess for 11M style AM a Uniden/Cobra is best. I still have a couple Grant XL's and a 66.

I hear the amature type AM is best with some of the older gear. QRN seems to have made a post on here about quality AM, maybe he'll share his experience.
 
I've tried mine on AM from time to time and have received compliments. Now I wasn't talking to the guys trying to do broadcast quality AM...those guys are way to picky for me.
 
I needed the 6 kHz chrystal filtre in thee FT 100, now it performs very fine
Getting excellent reports on thee old timer AM nets, setting up the tranciever for 25 watts carrier and just over 100 watts modulated.
 
An ASTATIC will make a HUGE difference but I will say I own several HF rigs and have owned numerous rigs and they all are different and will require different Mics like Sadelta D104 Turners ETC to get what your after as far as sound. Its basically all trial and arror on the air with honest reports. I know my new Yaesu FT-450 and my Yaesu FT-990 both have settings for audio the FT-450 has a built in Equalizer where the FT-990 has a hidden menu setting for audio tone quality. I personally have never heard an HF rig sound like and Export on AM but then look at what the 2 radios are built for I reallyu am not an AM user but know that HF rigs with ASTATIC and SADELTA mics sound fine that includes my Kenwoods aswell. I think my wifes Kenwood TS-50 mobile actally sounds good on AM aslong as its set in the low setting for audio or ofcourse its overdriven in the audio section but for a stock mic its actually pretty amazing how that little thing sounds
 
was just curious if anybody did much 10m (or even 6m) AM, using modern hf rigs, not good ole plate modulated antique transmitters, and how they obtained much, if any, quality AM audio. i have never heard MY 706 on AM, but have used it for dx on AM. i have not been told it sounds 'bad', but wondering how to make it sound good. read into 'dave-grant'. i know how to make an AM cb sound good, and that low level modulation with some carrier injected into the upper sideband will never duplicate it.......
 
Trouble with 6 meters is that conditions have always been so marginal, only CW and SSB type of modes can make contacts. The conditions really need to be strong for AM or FM on 6 meters. The same applies to 10 meters, but E skip has been strong at times to allow AM & FM there.
HF rigs on AM will only be adequate, and never "loud & proud" like CB radios are. The reason is CB radios using an audio amplifier (like the TA7222AP) to modulate the collector voltage on the finals. This is why CB radios have Public Address function, because its using the same audio amplifier that was used to modulate the voltage to the finals.

HF rigs have one more handicap, and that is the speech processor can be turned off which results in low audio. Also Japanese radios often have a switch on the microphone to aid spoken japanese, which results in muffled audio in for spoken english.
 
saw a post on qrz today that got me thinking. tried mine on AM & got the same results he did-'so-so' at best on AM. anybody use one here on AM? how does it perform there? did you do anything to MAKE it perform well?

Probably the most important things you can do is turn the speech processor OFF and make sure the carrier is set to NO MORE than 25 watts. That will help the sound quite a bit. Run the ALC so that the meter barely moves. If possible inject the audio into the AUX jack on the back. There is a provision for this and is generally meant to be used when running data modes. You will need to boost the mic level in order to get the proper modulation level. This bypasses all the mic EQ circuits that tailor the audio for simple two way communications.I ran my Icom IC-735 that way and it sounded GREAT.Try a few differant mics as well especially those meant for PA or broadcast use as they have a better freq response to begin with.

QRN seems to have made a post on here about quality AM, maybe he'll share his experience.

Still looking for that post. :confused:
 
The 706 ain't THAT bad on AM. I used to be fairly regular in the mornings on 7290 AM with mine. It isn't the best quality AM, but it will do if it is set right. I set mine with a scope and back to 25 watts to allow "head" room. That's one of the troubles with AM. A lot of people get just so upset if they don't see "swang" with an AM signal, and that really isn't the way to do it. A properly modulated AM signal will have little or NO "swang". I had a ball on 10 AM during the last cycle also in the mobile.


73

CWM
 
to QRN, CWM, et al, OK. a few ideas to play with. like i said, i wasn't told it sounds bad, and i know it isn't a galaxy(YUK), just wanted to see what i could do to improve over how i currently run it on AM. just picked up an ICm from heil which may or may not be an improvement over the shure 526t....that i have yet to try. the sm20 is horrible though on AM, & the stock mic gets far better reports on SSB. yes, the ALC meter on my 735 doesn't move when i talk on AM either, and it sounds real good with the 526t. there seems to be issue with the rear mounted carrier control knob though(age?) as i need to readjust it almost every time i turn the radio on. on the 706, i do seem to see less then 50 watts PEP when the carrier is set to 25 watts, which increases to almost 80 with the compressor on.
'Trouble with 6 meters is that conditions have always been so marginal, only CW and SSB type of modes can make contacts. The conditions really need to be strong for AM or FM on 6 meters. The same applies to 10 meters, but E skip has been strong at times to allow AM & FM there'-i and i'm sure plenty others will disagree with that, dudmuck. ONLY CW & SSB CAN MAKE CONTACTS ON 6 METERS? no, i have logged over 150 AM E skip contacts with under 5 watts carrier on 6 meters into either a squalo or mfj 3 element yagi. as for 10 meter AM, at roughly the same level.....probably closer to a million. i was just looking to increase those #'s if i can improve AM audio at all.
 
QRN is right on the money. I'd like to add that most manufacturers say to set the carrier level to 40 watts. THIS IS DEAD WRONG. It leaves NO headroom and will severely tax the cooling system (not to mention the power supply) of your radio, especially when you set a brick on the key and talk for 4 minutes straight as some AM ops love to do.

AM on a solid state rig can be done but as Dirty Harry said "A man's gotta know his limitations".

You are limited in the amount of carrier you can run due to heat and component selection in the final. You are limited in the amount of modulation you can run due to component selection in the final, power supply limitations, heat considerations and signal quality. For example, let's suppose you do run the 40 watts carrier. Now you start trying to add modulation. You can add modulation up to a point, and then you will hit the limit of the transistors or power supply and guess what? The radio begins to hit the wall so to speak--the carrier, which has remained at 40 watts drops on modulation because the radio can't supply 40 watts to the carrier plus the added modulation.

So you have to balance out everything. Run enough carrier and modulation to be heard, but not enough to blow the whole thing sky high or have a meltdown, or sound like crap. And once you find the sweet spot LOCK THOSE CONTROLS DOWN AND DON'T TOUCH THEM.
 
Big signals comes from knowing what amp to buy. :D

Or build!!!

In thinking a little bit more, I'd be willing to say that across the board, the average Solid state transceiver can be accurately marketed as a stand-alone digital, SSB, and CW radio, but is only good (as far as AM is concerned) as an exciter for an amplifer.
 
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