Realistic TM-1001

someone else's unit with blue LEDs illuminating the meters
(modified) generic image

This was a where-is-as-is item for $100 from a local Radio Shack store.   
For sometime I'd been considering getting a Heath unit (AJ-12) to replace 
that awkward SX-62 setup (it was also still being used some on 30-50 MHz  
along with an SP-600 until I got a Bearcat Scanner in Aug 1979 - even     
after that I still needed something with AM for BBC and French TV audio   
at 41-MHz).                                                               

specifications    schematic

The 7" sliderule dial (after 3" ones on my prior units) was like heaven - 
I could actually read the 0.2-MHz channel increments on it!  It wasn't too
long before I had replaced the small tuning knob with a large surplus spin
knob to permit more rapid tuning.                                         

Even with its stock (180-kHz ?) i.f. filters the selectivity was good.  I 
did have problems the first year with the tuning shaft freezing up (lots  
of forced lubrication and vise-grip torquing to "fix" that).              

The meter lights didn't last long - I soon had a 6-v #47 for the s-meter. 
That gave way to "white" LEDs (as did the dial lights when they eventually
died).  Needing frequent access to its innards finally led to me leaving  
the cabinet and faceplate off the unit for the last few years of its use. 

The main power supply failed in Feb 1989 - a pair of 6-v lantern cells    
were used until the 12-v dc Micronta could be set up to feed it (after    
that the multipath meter was no longer functional).                       

The dial cord had to be restrung a few times (and the use of a rosin      
no-slip compound resorted to).  As time went on, the mechanical tuning    
system became less robust with backlash, etc.                             

Intermod overload did not become a major problem until after several      
100-kws were situated at Galm Road (9-mi wnw of me) - in the late 1980s.  
A step-attenuator was resorted to when beamed that way (along with a      
Winegard FT-7600 trap tuned to 97.3).                                     

In Jun 1990 two 150-kHz were put in (with Molex connectors for sockets).  

In 2000 a Conrad RDS Manager was added (audio out into it) and produced   
jaw-dropping results.  By late 2001 it was modified so that it could feed 
a DOS program on a 1992 386-SX-16 to display the hexadecimal PIs.  Oddly, 
that program would not run on "faster" machines, and other Win-based      
programs wouldn't work with it.                                           

Some good-faith but aborted attempts in 2006 and 2007 were made to get    
something more modern.  Meanwhile, some 110-kHz filters replaced the      
150-kHz pair in the narrow-band setting (without any negative effects on  
RDS as had been feared).                                                  

In Jun 2008 an XDR-F1HD replaced the TM-1001, and I lost access to PI     
decoding.  Ironically, only a week before I'd discovered a mod to the     
cable feed that would permit the Conrad to now work with those Win-based  
RDS programs!                                                             


Page Created: Jun 16, 2011