The AM Forum
March 28, 2024, 05:26:30 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
 
   Home   Help Calendar Links Staff List Gallery Login Register  
Pages: [1]   Go Down
  Print  
Author Topic: KE1GF Icom 706MkIIG Mobile TX audio and RX Selectivity Mods  (Read 40181 times)
0 Members and 1 Guest are viewing this topic.
KE1GF
Guest
« on: June 14, 2005, 12:28:10 PM »

http://home.comcast.net/~ke1gf.web/706_Mods/index.html
Logged
WD8BIL
Contributing
Member
*
Offline Offline

Posts: 4409


« Reply #1 on: June 14, 2005, 01:16:59 PM »

Nice Job Bill !!

It sounds great from the mobil setup.
Logged
W6FO
Guest
« Reply #2 on: July 20, 2005, 10:13:57 PM »

Bill:

There seems alot of different mods out there for the 706MkIIG.  Can you help me sort it out and figure out the best way to improve both AM reception and TX on my stock IIg?

Thanks

- JT
Logged
K1JJ
Contributing
Member
*
Offline Offline

Posts: 8893


"Let's go kayaking, Tommy!" - Yaz


« Reply #3 on: July 20, 2005, 11:05:42 PM »

As usual -  Nice Job, OM!  

You definately spent the time to do the finer details. Lots there. And,
the documention and circuit mod descriptions are EZ to follow. This
write up will probably be around for years as the standard for
modifying this rig. When the web robots get it, it will help lots of guys
outside the AM community too.  It's in the same class as the DUQ
mods for the FT-1000D.

Make sure G gets it into the archives for EZ access.

73,
T
Logged

Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

Wise Words : "I'm as old as I've ever been... and I'm as young as I'll ever be."

There's nothing like an old dog.
KE1GF
Guest
« Reply #4 on: August 01, 2005, 04:35:41 PM »

Quote from: W6FO
Bill:

There seems alot of different mods out there for the 706MkIIG.  Can you help me sort it out and figure out the best way to improve both AM reception and TX on my stock IIg?

Thanks

- JT


TJ the best way to improve the TX audio is do my audio stage mods. The tough part about the 706 is finding the FL-102 IF filter for better RX selectivity. I have two of them here and I have two 706MkIIG's. Keep looking on ebay, they pop-up and get scooped up quick.

I would like to find a filter that would pop into the 706MkIIG for 6KC am selectivity, but the problem is that ICOM never provided provisions in configuration menu's of the 706 for a more selective AM IF Filter. You wouldn't even need to perform any circuitry changes to the radio if the software could do it, there's nothing missing in the radio to do, I just have to hack the rig to do the job...

I have demonstrated that it is possible to place a better filter into the radio with mods, but no company will manufacture a filter for the rig if it requires serious mods to make it work.

-Bill 'GF
Logged
kc2ifr
Guest
« Reply #5 on: August 03, 2005, 05:48:07 AM »

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=5795337655&ssPageName=MERC_VI_ReBay_Pr4_PcY_BID_Stores
Logged
WA1GFZ
Member

Offline Offline

Posts: 11152



« Reply #6 on: September 13, 2005, 12:02:51 PM »

Every receiver I have seen with crystal or mechanical filters do not take advantage of the total performance of the hardware. I have found it takes at least 2 filters cascaded with shielding performance to match. Say you have a rX with 100 dB of dynamic range and a filter with ultimate rejection of 70 dB
guess what is the limit for performance.  Harris and Racal both use dual filters in the first IF for roofing. The filters are located in different shielded modules
to take advantage of the possible performance. Cascading filters in the second IF will also improve performance as long as the passband ripple is acceptable. This helps when there is noise or QRM.  gfz
Logged
KE1GF
Guest
« Reply #7 on: November 09, 2005, 09:58:50 AM »

Anybody thinking of doing my mods in the future...

snatch this up: http://cgi.ebay.com/Icom-FL-102-6kHz-AM-filter-9mHz-6dB-Excellent-shape_W0QQitemZ5826029893QQcategoryZ48702QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

The price is good...

-Bill 'GF
Logged
KE1GF
Guest
« Reply #8 on: February 09, 2006, 01:07:49 PM »

Hey Crew, sorry for the downtime I moved my site over to my comcast webspace.

-Bill 'GF
Logged
KE1GF
Guest
« Reply #9 on: March 26, 2006, 01:41:44 PM »

Okay, here's the new address.

I don't suggest that you do this mod until I find out what went wrong with the 706 that I gave to Rich K1ETP.

http://unix-srv.1gflabs.com/ke1gf/706_Mods/index.html

-Bill 'GF
Logged
kd7ugy
Guest
« Reply #10 on: January 04, 2010, 05:06:00 PM »

It seems that the latest link isn't working, is there any way to view these modifications? Also will they work on the older IC-706?
Logged
Ralph W3GL
Contributing
Member
*
Offline Offline

Posts: 748



« Reply #11 on: January 05, 2010, 01:11:02 AM »

Bills web  site is no more, the only place I see him on line is Skype.
ke1gflabs is his Skype name...

Good Luck!  I just checked and he appears as being on line.
Logged

73,  Ralph  W3GL 

"Just because the microphone in front of you amplifies your voice around the world is no reason to think we have any more wisdom than we had when our voices could reach from one end of the bar to the other"     Ed Morrow
KE1GF
Guest
« Reply #12 on: March 01, 2010, 03:25:35 PM »

There is nothing wrong with my mods, you just have to run a little bit more than 8 watts carrier on AM.

http://webpages.charter.net/1gflabs/706_Mods

-Bill 'GF
Logged
DMOD
AC0OB - A Place where Thermionic Emitters Rule!
Contributing
Member
*
Offline Offline

Posts: 1768


« Reply #13 on: March 01, 2010, 11:49:39 PM »

Hi Bill,

Have you tried running audio to the modulator input via the accessory jack?

Do you happen to know if this modulator input goes to the same place as the microphone audio?

Thanks

Phil - AC0OB
Logged

Charlie Eppes: Dad would be so happy if we married a doctor.
Don Eppes: Yeah, well, Dad would be happy if I married someone with a pulse.NUMB3RS   Smiley
Pages: [1]   Go Up
  Print  
 
Jump to:  

AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
 AMfone © 2001-2015
Powered by SMF 1.1.21 | SMF © 2015, Simple Machines
Page created in 0.072 seconds with 19 queries.