TS-50 LCD display backlight

[N2EIK]

I figure someone may want this info. My backlight became intermittent and then after a couple months completely out.
What I have found was a leaky SMD capacitor on the display board. 47uf@16v. The fish oil eats thru one or more traces between the cap and the regulator transistor. You have to carefully remove the cap (it may even just fall off), clean the board really good with denatured alcohol, lightly scrape the paint off the traces and repair any open traces with a single thin strand of bare wire and solder in place. Then replace the cap, SMD is not needed, a small profile 'lytic will fit.

[N4NYY]

Good deal. I had caps leak on a TS-850 display. Then I found find out that the TS-850 is notorious for leaking electrolyte and eating traces. I stepped up the caps to the next highest voltage (16V replaced with 25V).

I do not know why Kenwoods had so many problems with leaking caps.

[KE3WD]

Wasn't just Kenwood.  Many electronic mfrs had to put up with the bad pr of those darn Chinese made caps.  The problem has since been solved, but there was a period of time in which the Chinese caps were using a bad electrolyte chemistry.  Believe it or not, traced to a chinese worker who thought he had stolen the formula from a Japanese firm, only the firm had left a key ingredient out of the recipe hidden in their safe.  Heh. 

Anyway, that period has passed, today's Chinese made caps are of fairly good quality.  There will be, of course, units produced during that time period that will have caps that may exhibit these kind of problems.  And it can be in *any* brand.  I see it all the time at the test bench every day in every sort and manner of electronics.


73

[KE4DRN]

hi,

I have photos of the pc board and the location of the leaking cap on
the yahoo ts-50 group photo section.

http://groups.yahoo.com/group/Kenwood_TS50/

The ts-60 can be repaired the same way.

73 james

[KA4DQJ]

Glad you got it fixed.  The backlight failure is common on the TS-50, and I've seen several causes and fixes on the Web; one involved drilling bigger holes.  Some years ago I had a TS-50; worse rig I ever had.  Seems every time I turned it on something else was malfunctioning, and worse I couldn't fix the problem.  I had the backlight problem too... never could fix it.  The 5v was there, and the filaments were good.  

I actually got so disgusted after a year that I tossed the thing in the garbage.  A couple days later I was on Netlogger messenger and got to talking about the thing, and N0GUE, a total stranger begged for the rig... wanted to buy it.  I told him I couldn't take money for junk, and wouldn't be doing him any favors giving it to him.  But, I dug the TS-50 out of the garbage bag and sent it to him completely free.  I think the guy was a pretty competent tech, but I told him for every problem he managed to fix, two more would spring up.

Six months later I emailed him, and he was still working on the thing... doing something with capacitors.  Poor guy.  I've owned a lot of quality Kenwood gear over the decades, still do in fact, and each rig has been wonderful.  I don't know where my old garbage TS-50 is today, but wherever it is I'd bet hard money that it isn't on the air.  

[K4JJL]

I usually replace leaky polarized electrolytics with tantalums.  I even assembled my Arcom RC-210 with tantalums instead of electrolytics.  I tossed the electrolytics that came with it in the garbage.