• Kenwood Ts 940 For Sale
• Kenwood Ts 940s

Hi,My 940 was working good for while, but now the S-Meter lights and theVFO display have started to flicker. They flicker at random times veryquickly (all at once). The LCD display bulbs don't flicker, but theyhave both burnt out now. And I just replaced them less than 2 years ago(with Kenwood factory replacements).I checked the voltage to the power amp and it reads 28.6 volts. TheS-Meter (lights) read 13.6 volts and when the flicker occurs thevoltage very quickly varies from 6 to 13 volts - never above 13.6volts.

Is this some kind of voltage regulation issue? Rollercoaster tycoon 3 download ocean of games. I can't get itto do this by moving wires around and pushing on things.

It does onlyseem to effect the lights the are controlled by the dimmer switch.On a side note, I've been reading several posts about the 2N5885 thatregulate the 28v supply for the power amp failing and wiping out theMRF-485 transistors that are no longer available. Does it make sense topreemptivly change the 2N5885 transistors to help prevent damage tothose MRF-485?

I use my 940 daily - and its on most of the day.-Scott,WU2X. Wrote in messageoups.com.Hi,My 940 was working good for while, but now the S-Meter lights and theVFO display have started to flicker. They flicker at random times veryquickly (all at once). The LCD display bulbs don't flicker, but theyhave both burnt out now. And I just replaced them less than 2 years ago(with Kenwood factory replacements).I checked the voltage to the power amp and it reads 28.6 volts. TheS-Meter (lights) read 13.6 volts and when the flicker occurs thevoltage very quickly varies from 6 to 13 volts - never above 13.6volts. Is this some kind of voltage regulation issue?

I can't get itto do this by moving wires around and pushing on things. It does onlyseem to effect the lights the are controlled by the dimmer switch.On a side note, I've been reading several posts about the 2N5885 thatregulate the 28v supply for the power amp failing and wiping out theMRF-485 transistors that are no longer available. Does it make sense topreemptivly change the 2N5885 transistors to help prevent damage tothose MRF-485? I use my 940 daily - and its on most of the day.-Scott,WU2XScott,May I suggest the TS-940 web page? Jeff King ZL4AI / DU7 (N5IW also hasone)One stop shopping for almost every issue, mod or change noted for the TS-940The web page is so big - it is in 2 parts!The power supply, as you have noted, has been an issue for other operators.Kenwood TS-940s AVR board, by N0XWR on February 28, 2006You won't find an AVR board for sale new - you should endeavor to fix theone you have.First, check regulator Q103.

It is in the rear left corner of the rig as therig faces you. It is on the heatsink for the power supply. There are threeregulators side by side. It is the one on the far left. No matter whetheryou replace it or it is good, it is imperative that you cut the connectoroff of the three wire harness that plugs on to regulator Q103 and solderdirectly to it.

Kenwood Ts 940 For Sale

This harness comes from plug-in #2 on the AVR.Over time the connector overheats and fails and cannot carry the 20-30 voltsto and from that regulator. I have seen the problem many, many times. Whenthe connection to that regulator fails, it takes out Q6 on the AVR board, socheck it next.Clif at AAvid Electronics, (now back in repair business at) helped me get through the problem. Also check D3, D9and D14 which are zener diodes on the AVR board.

Kenwood Ts 940s

They can be checked righton the board with a multimeter. The board can be removed easily. As youunplug the wiring harness use a sharpie and number each connector so thatyou can reinstall it easily. Make a diagram, too. Use small long noseforceps to unplug the connectors to the AVR board.Incidentally, Q103 is part # NTE377 available at Mouser. Q6 is part # NTE382also available at Mouser.I have the part numbers for the zeners if you need them.73s Jerry N0XWR.