[Kenwood] RE: TS-850 or TS-870

[Hsu, Aaron (NBC Universal)]

Warren,

I haven't had much operating time behind the '870, but I do have two '850's (and sold a 3rd a few years ago).  I contemplated "moving" from the '850 to the '870, but decided against it as the '870 didn't warrant the expense.  I based my decision on in-store demos of the '870 and many reviews/comments on the 'net.  Here's my 2 cents...

>>> Which is best at rejecting adjacent interference?
Comparing "stock" rigs, the '850 definitely has better selectivity.  The main problem with the '870 is a lack of good filtering in the front end before the DSP chain.  However, there are mods out there that add better pre-DSP filtering to the '870 and reports are good.  However, the '850 wins due to it's "mod-less" nature.

>>> What are average price ranges for one in good condition?
I've seen "good" '850's currently going for $700 to $800.  Haven't seen any '870's for sale in a while...they're not as common as '850's.  I'd expect them to be in the $800 to $1000 range.

>>> Is the 870 worth the extra money?
Not unless you want a "newer" radio and have the time to mod it to improve selectivity.

>>> Any reliability issues with either model?
The '850 has a well known problem with a leaky memory backup battery - the acid eats through the PC board traces and renders the rig dead.  Easy fix - replace the battery before it leaks or replace the battery and jumper the board traces.  Another problem is the DDS chip on early model '850's.  The fix is a bit time consuming as you need to replace the surface-mounted DDS chip with an updated one, but I'm not sure if it's still available.  Best way to avoid this is to buy a more "recent" model.  Sorry, don't have much info on the '870.

>>> What filters or options should be installed? 
For the '870, check the web for the mod on how to replace the stock ceramic filters.  For the '850, it depends on your operating modes.  I have one of my '850's configured with two 2.1KHz and a 400Hz InRad filters, and the second rig configured with a 2.1KHz and two 400Hz InRad filters.  I think you can tell which rig is for which mode.

>>> Which do you like and why?
For me, the TS-850.  Better "out-of-box" performance and better cost factor.  Most all of the problems on the '850 are documented and can be found on various websites on the 'net.

>>> What is the best serial number range to get?
To avoid the DDS problem on the '850, find a newer one.  I believe the old DDS chips were only used in the first and second year of production, so serial numbers starting with "4" or higher should be fine (the first year of production started with the number "2").

Anything else to look for or beware of?
Beware of "hacked" radios.  As mentioned earlier, the '870 can be greatly improved by some mods.  However, if these mods were done by an amateur (no pun intended), the rig could be compromised.  Same with the '850.  For both rigs, make sure you ask for a complete service history and what mods/hacks were performed, if known.  Also ask if the rig was ever serviced/modded as some "revert" mods to make it sellible as "stock".  Good mods to have in the '850 are the updated DDS (early models) and replaced backup battery.  And, if you can find an un-modded DSP-100 unit, it'll make your '850 sound very sweet.

As always, these just my humble opinions and YMMV.


73 and have fun!
  
  - Aaron Hsu, NN6O (ex-KD6DAE)
    {nn6o}@arrl.net
    {aaron.hsu}@nbcuni.com
    No-QRO Int'l #1,000,006
    . -..- - .-. .-   ".... . .- ...- -.--"