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FT857D - UHF CB conversion

Posted: Thu Apr 29, 2010 8:37 am
by VK4TS
OK not asking for a flame war -

Is it possible YES or NO ?

Is it simple YES or NO ?

Re: FT857D - UHF CB conversion

Posted: Thu Apr 29, 2010 10:26 am
by VK4GHZ
Trent, appears not.
http://www.kb2ljj.com/data/yaesu/ft-857.htm

The MARS mod stops at 470MHz, which is consistent with most late model Yaesu UHF radios. :cry:

Re: FT857D - UHF CB conversion

Posted: Thu Apr 29, 2010 2:08 pm
by VK4TS
OK I need to find out more - i have one email reference that will take them to 512 Mhz - just thought it would be handy to listen while cruising the country side

Re: FT857D - UHF CB conversion

Posted: Thu Apr 29, 2010 2:23 pm
by VK4GHZ
Trent, I think you will find it receives to 512MHz http://www.hampedia.net/yaesu/ft-857.php, but is only capable of TX to 470MHz.

So yes, RX on CB, TX no.
Easy to do: depends on your SMD skills, but generally yes.

Assuming there aren't sensitive little ears in the car, monitoring 477.400MHz is a no-brainer out on the highway... have been made aware of many speed cameras. :wink:

:D

Re: FT857D - UHF CB conversion

Posted: Fri May 07, 2010 8:05 am
by VK4TS
Even though this site refers to 512 Mhz coverage..

http://www.hampedia.net/yaesu/ft-857-mars-mod.php


Try a google for 857D 420-512 and there are heaps of sites - -maybe the original info was wrong and its been perpetuated by lazy site owners..

I really just want to monitor 477 but cant see where this is done...I have the region tables but none describe the 512mhz - Did the FT100D cover 512 and this is where is came from

Re: FT857D - UHF CB conversion

Posted: Fri May 07, 2010 5:35 pm
by VK2HRX
If you want to monitor 477MHz, why dont you try tuning the VFO to 477MHz.? I think they do this straight out of the box. Mine (857D and 987D) both do

Compton
VK2HRX

Re: FT857D - UHF CB conversion

Posted: Fri May 07, 2010 7:38 pm
by VK4TS
AH HA = Mine doesn't - it stops at 470 mhz you are the first person I have come across who admits to a 857D that covers 470mhz +

Can you please give us some clues ?

Does the rig have two PL259s or one 259 and one N type...

Was it a VK purchase or are they from O/S ?

Do you know what region settings are inside the rig ?? Jumper settings ??

Could you advise the Serial number sequence ?? First 4 digits ??

Trent VK4TI

Re: FT857D - UHF CB conversion

Posted: Fri May 07, 2010 8:40 pm
by VK2GOM
Hi Trent,

Just for info, mine was from VK, has an SO239 and N on the back, and tunes from 420 to 470 MHz - no further, no less.

There are a bunch of band setting solder blobs but I haven't touched it. I would have thought opening it up to full Tx/Rx was easy enough given info on the net. I did my VX-6R for instance... but did notice some 'instability' in memories and the rig locking up, so I reverted back to standard.

73 - Rob VK2GOM / G0MOH

Re: FT857D - UHF CB conversion

Posted: Sat May 08, 2010 8:57 am
by VK5FGMH
Found this on the www

http://www.rigpix.com/yaesu/ft857-897_modcollection.pdf


Cheers Tony
VK7FGMH

Re: FT857D - UHF CB conversion

Posted: Sat May 08, 2010 12:50 pm
by VK2TDN
VK7FGMH wrote:Found this on the www
http://www.rigpix.com/yaesu/ft857-897_modcollection.pdf
Cheers Tony
VK7FGMH
the link doesnt work tony :(

ERROR 404

Oooops!
The page you're searching for does not exist.
It may have been moved, renamed or permanently deleted.

Please go to the main page and try again.
Best 73 de Janne/SM0OFV


cheers
Dave

Re: FT857D - UHF CB conversion

Posted: Sat May 08, 2010 1:01 pm
by VK2GOM
Something weird going on here... if you go via the Rigpix main page, click on the FT857D, then click on the link, it works.

If the hyperlink is pasted somewhere else (as it is here) - it doesn't.

What does work though is right mouse button on the link as shown here, then 'save target as' - that works.

No idea why - but I downloaded the document fine from the http://www.rigpix.com main page, then navigating to Yaesu > HF and more > FT857D

73 - Rob VK2GOM / G0MOH

Re: FT857D - UHF CB conversion

Posted: Sat May 08, 2010 5:42 pm
by VK5FGMH
Copy and paste into address bar and it works.

Interesting article, has required info for free band mod.

Tony VK7FGMH

Re: FT857D - UHF CB conversion

Posted: Sun May 09, 2010 8:01 am
by VK4TS
Its an excellent article about the 857D - the frustrating thing is this site again refers to 512 coverage of the 857D....

Hopefully we will get some clues from VK2 today about the model vintage etc of his so we can work out how to receive the UHF CB band.......

Re: FT857D - UHF CB conversion

Posted: Sun May 09, 2010 8:49 am
by VK2GOM
It might come down to something as simple as unsoldering the Profanities Filter in the Lo chain. Then all CB frequencies will be received.

HI :lol:

73 - Rob VK2GOM / G0MOH

Re: FT857D - UHF CB conversion

Posted: Sun May 09, 2010 12:55 pm
by VK6SIX
From memory,

Yaesu have used masked eproms for many years

Also there appears to be 16 worldwide versions of the ft 857.

Re: FT857D - UHF CB conversion

Posted: Sun May 09, 2010 12:56 pm
by VK2CSW
If I remember correctly, which at times is a stretch, aren't there a couple of versions of the 857D?

I seem to recall there being a US, European and "other" versions. I don't know the details but it was band selection that was the major differences.

When I get back home, I will see if my 857D will get there. Funnily enough I've never looked outside the Amateur bands with it before.

Colin

VK2CSW

Re: FT857D - UHF CB conversion

Posted: Mon May 10, 2010 5:26 pm
by VK2HRX
Well Bu&*er me> I just tried the 897 and you're correct it wont go past 470MHz on Rx. I was totally sure I had used it to monitor 477 stuff in the car. I must have been using the FT8800 instead. Sorry to those I misled and just goes to show you cant trust everything you read on the internet! I checked the specs out of the manual supplied with the radio and it nominated 470 MHz not 512MHz. I'll keep using the FT8800 I guess.
Compton VK2HRX

Re: FT857D - UHF CB conversion

Posted: Fri Mar 29, 2013 5:54 pm
by VK4FLR
Just curious regarding the discussion re the FT857D RX coverage above 470mhz - has anyone successfully modified one to go beyond 470mhz ? - a lot of reviews on a Google search say RX coverage to 512mhz - I only want the RX coverage to about 480mhz - & do not want to open up the TX range. The only reference I can find is a small software program -SOFTJUMP.EXE Version 0.2 but hesitant to run this into the Rigs firmware & I think it is just a software patch instead of the hard wired jumpers anyway for the TX open up mod ?

Just strange that the RX is restricted to 470mhz ? My 847 goes to 512mhz rx no sweat ??
73
Frank VK4FLR

Re: FT857D - UHF CB conversion

Posted: Fri Mar 29, 2013 10:26 pm
by VK4XA
VK4FLR wrote:Just curious regarding the discussion re the FT857D RX coverage above 470mhz - has anyone successfully modified one to go beyond 470mhz ? - a lot of reviews on a Google search say RX coverage to 512mhz - I only want the RX coverage to about 480mhz - & do not want to open up the TX range. The only reference I can find is a small software program -SOFTJUMP.EXE Version 0.2 but hesitant to run this into the Rigs firmware & I think it is just a software patch instead of the hard wired jumpers anyway for the TX open up mod ?

Just strange that the RX is restricted to 470mhz ? My 847 goes to 512mhz rx no sweat ??
73
Frank VK4FLR
Hi Frank,
The software you have only worked on the very early firmware versions of the 857's, it wont work at all on the later versions.
AFAIK, no-one has gotten a late model 857/897 onto the UHF CB band.

Re: FT857D - UHF CB conversion

Posted: Sat Mar 30, 2013 9:41 am
by ZL3MF
I have the same problem with my FT7800 RX no problems but TX stops at 469.995Mhz. Does anyone know a mod for the 7800 to cover UHF CB or as we call it here in NZ PRS Radio. Have two teenage boys who have handhelds and would be nice to taklk to them from the car :D :D