[AMRadio] HRO50 dial cord


Bernie Doran qedconsultants at embarqmail.com
Sat Dec 5 11:48:07 EST 2009


I posted an info request a few days ago about dial cord replacement, Yes the 
panel must come off, remove all controls that penetrate the panel, remove 
all visible screws, then the big one. the two levers that hold the coils in 
place have a stud that passes through the panel and interior. they have a 
3/8 inch nut located about 1/2 inch above the chassis, somewhat difficult to 
get too.  on mine it was not the dial cord, rather the bronze bushing in the 
gear that is attached to the cord drum. The bushing was dry and nearly 
frozen to the gear, can not imagine why, its only 60 years old!    The force 
on the gear pushed it out of engagement range. getting the nuts back on was 
also fun, I used a piece of large dia solder bent at about a 45 degree angle 
and just long enough to hold the nut. position the nut at the end of the 
stud and then try to spin it with another long tool or wire. it will 
eventually catch and from there on its just dog work. The point of all this 
is if you have the front panel off for some reason, clean and lub that 
bronze bushing.  The tuning now is very smooth. believe it or not National 
used a spring loaded double brass gear, sure would not want any slop in the 
dial pointer!!!  shows again the quality of construction in the old stuff. 
The old stuff will still be working in another fifty or more years, the rice 
boxes are simple throw aways!!.  One more thing that might be of interest, 
all of my old receivers, HRO50-1, Drake R4, 75A2, 75A4, all are quieter and 
hear signals that my Ft1000MP mark V can not hear, in addition the Mark V 
hears things that are not there.  Same antenna connected in parallel and 
also seperated..  That just amazes me.   73 Bernie W8RPW 




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