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THE AM BULLETIN BOARD => Technical Forum => Topic started by: Ed WA4NJY on October 16, 2014, 07:41:12 PM



Title: ICOM IC-7200 vs Yaesu FT-450D
Post by: Ed WA4NJY on October 16, 2014, 07:41:12 PM

I would like to have a portable HF/6 rig that does a decent job on AM transmit.  Leaning toward the ICOM for several reasons but concerned with possible aggressive ALC like the PRO series.

 Any input will be appreciated.

Thanks,

Ed WA4NJY
Bradenton, Fl


Title: Re: ICOM IC-7200 vs Yaesu FT-450D
Post by: DMOD on October 16, 2014, 11:34:04 PM
My main SS ricebox tranceiver is an ICOM-7200 and produces great AM.

I also like the variable pass-band tuning for tuning out the nearby "quackers."

A local ham friend has a Yeasu FT-450D and we have never been able to get a decent AM signal out of it.

The IC-7200 is one of the few riceboxes built like a tank.

Phil - AC0OB

 


Title: Re: ICOM IC-7200 vs Yaesu FT-450D
Post by: Ed WA4NJY on October 17, 2014, 07:52:32 PM

Hi Phil,

Thanks for the reply.  I now have an IC-746PRO which is fine for what it is.  I am liking the AM receive a bit more lately.  The AM "fidelity" reports are not too bad.  It is the power level that bothers me.

If I lower the radio's power level to give me 100 watts of carrier with the amp, the voice peaks become very low.  Even barefoot and radio carrier level at 20-25 watts,  the peaks are 55 watts.

What does the 7200 do on voice peaks?

This is only for casual AM when I am too lazy to fire up the tube rig.

Thanks again,
Ed


Title: Re: ICOM IC-7200 vs Yaesu FT-450D
Post by: Pete, WA2CWA on October 17, 2014, 08:02:45 PM

Hi Phil,

Thanks for the reply.  I now have an IC-746PRO which is fine for what it is.  I am liking the AM receive a bit more lately.  The AM "fidelity" reports are not too bad.  It is the power level that bothers me.

If I lower the radio's power level to give me 100 watts of carrier with the amp, the voice peaks become very low.  Even barefoot and radio carrier level at 20-25 watts,  the peaks are 55 watts.

What does the 7200 do on voice peaks?

This is only for casual AM when I am too lazy to fire up the tube rig.

Thanks again,
Ed

If you want better AM fidelity (better lows and slightly better highs) with the 746PRO, there is a high impedance input directly to the modulator. It's pin 4 of ACC1. Note that the front panel mike gain control will not have any effect on your audio level with this connection but it's a great place to connect an audio equalizer or a dozen different audio boxes between your mike and modulator input. I haven't used the front panel mike input jack on my 756 PRO II for years.


Title: Re: ICOM IC-7200 vs Yaesu FT-450D
Post by: KD6VXI on October 17, 2014, 08:33:18 PM
Almost any ricer will sound good set up with the alc voltage mod.

I used my ft857 exclusively and got good audio reports,  even from TimTron.

It's been discussed numerous times here.

--Shane
KD6VXI


Title: Re: ICOM IC-7200 vs Yaesu FT-450D
Post by: K9DXL on October 17, 2014, 11:27:38 PM
FWIW, I have an IC-7200 and it's my only SSB rig.  A lot of bang for the buck, solid construction, and DSP functions that really work.  I have no experience with the FT-450D, so won't say more except that I like the ICOM a lot.


Title: Re: ICOM IC-7200 vs Yaesu FT-450D
Post by: Pete, WA2CWA on October 18, 2014, 01:15:42 AM
Almost any ricer will sound good set up with the alc voltage mod.

--Shane
KD6VXI

There are pros and cons to using ALC voltage mod that's been floating around the internet for years. I've tried the voltage mod on both the Icom 756 PRO II and the IC-7000. On the receiving end on several tests, the fidelity didn't change whether I used it or not. However, with the voltage mod, it was easy to overdrive the amp into distortion on audio peaks.

I've worked several stations on 20 meters AM that were using a FT-450D and stock mike. One was running barefoot and one was driving an amp(don't remember what amp). Both sounded fine.
AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands