[Yaesu] Kenwood TS-940 CAUTION!

[KC3VO at aol.com]

They are both nice radios, but the KENWOOD is likely to become an expensive  
paperweight if you have a failure of the DRIVER TRANSISTORS in the R.F. power  
amplifier!  The plastic cased, "flat-pack" MOTOROLA  24 volt devices  used in 
this radio have not been manufactured for many years, and FINDING a  
suitable, "Low-beta, Matched pair" is about like finding a winning lottery  ticket! To 
my knowledge, there are NO substitutes that will PHYSICALLY and  electrically 
fit the position.  Often, due to cooling fan failure, power  surges, or other 
causes, the POWER SUPPLY pass transistors in the 940 will  SHORT, placing 
approx 40 volts onto the 24-28volt circuitry, resulting in the  DESTRUCTION of 
these parts, which can render the radio useless, as far as  TRANSMITTING is 
concerned. I WOULD NOT pay much for one,( UNLESS it came with  SPARE driver 
transistors!)--NOW you have the info, the DECISION is, of course,  up to you, but 
this type difficulty is ONE of the HAZARDS of buying OLDER  RADIOS.   Even the 
radios such as the ICOM IC-706,  YAESU FT-920,  and FT-100  have been affected 
by this Non-availability of MOTOROLA  transistors. (The ICOM and YAESU used 
the #MRF-255 transistor, which is no  longer being made, although there ARE a 
few still available, but at higher than  normal prices.--73, and GOOD  
LUCK!-----------------------------------------------------------------------------------
--------------------------------KC3VO,  Bob