[Johnson] Ranger fuse -- where?

K6JEK k6jek at comcast.net
Thu Jun 29 13:45:30 EDT 2006


Where do you put the fuse in a Ranger?   That's the question I've asked 
at the end of the periodic discussions on this forum about the dangers 
of the two-fuse plugs on Rangers.   I've been convinced for a long time 
that safety trumps authenticity and have intended to replace the 
dangerous two wire, two fuse AC mains connection with a three wire 
cord.   But where to put the fuse if not in the plug?   No one ever 
answered that for me.

Procrastination was finally ended when working on a stubborn hum on the 
RF problem (not from the modulator!) I noticed in my repeated plugging 
in and unplugging that the cord was coming out of the plug.   It was 
time to replace the cord. The fuse question could wait no longer.

Here's the answer, at least my answer.  Put the fuse holder where the 
AC cord comes in.  Move the cord next to the relay socket on cabinet 
side.   Move the solder lugs that were there over to the other side 
under the nuts holding the terminal strip on that side.

The hole formerly for the AC cord now for the fuse holder must be 
slightly enlarged to 1/2" and a new hole must be drilled for the cord.  
I put this hole level with the screw for the relay socket midway 
between the socket and the edge of the cabinet cutout.  I'd penciled 
the location of the cutout on the chassis when the Ranger was still in 
the cabinet.    I used a circular Heyco strain relief that required a 
smaller hole that the more familiar clamping Heyco.     I was careful 
to miss the relay socket.   If I were doing it again, I'd move the hole 
a little farther away from the relay socket to miss that socket by a 
little bit more.

The solder lugs are removed from the nearby hole and moved across the 
way to the terminal strip that hosts the RF chokes leading to the AUX 
socket.   The  bypass caps were clipped out and replaced with AC rated 
X1/Y2 caps, Vishay/Roederstein WYO series ceramic  disc suppression 
caps.

It's in.  It's neat.   I did drill a hole.   In this former basket case 
Ranger, museum quality isn't a possibility, originality not an issue.   
  I do have a nearly pristine Ranger II.   Since I use these things and 
like staying alive, I plan to do exactly the same thing to it.

Jon, K6JEK

PS:  Changing the power cord didn't fix the original hum issue.   
Shucks.



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