[CQ-Contest] $1000 receiver performance

[K3BU@aol.com]

In a message dated 3/11/2005 8:09:13 AM Eastern Standard Time, 
vr2bg at harts.org.hk writes:

>>Oh well - again, very interesting to see variation in experience
from comments posted here... such as 850-vs-870 as noted
by W6WRT.<<


The TS 870 becomes whole different radio if modified by replacing stock 
filters (especially 455 kHz Murata ceramic joke) by Inrad 2.1 kHz filters in both 
IFs. 
http://members.aol.com/ve3bmv/TS870mods.htm
Also early models had poor gain distribution along the RF path, too much gain 
up front causing intermods from strong signals and then poor DSP was so 
confused that it gave up :-)
Later Kenwood had updates in the software, change the gain distribution and 
when filter mod is done, it is like class higher radio. Another nice thing 
about 870 is that with VHF handhelds and their special interface it can be 
remotely controlled, which is ideal for any antenna tests and measurements using 
remote site.
870 has excellent DSP in the IF, except the designers neglected the strong 
signal immunity in the preceding stages. 
Another weakness is the shaft on the main VFO encoder, with time it gets 
"tired" develops play and VFO starts skipping. In order to prolong its life it is 
advisable not to lean or rest your hand on to the main tuning knob, but rather 
just turn it from below.

73  Yuri www.K3BU.us