The SM-512 is a service monitor that covers 1 to 512 MHz if memory serves correctly. It has a built in Sinadder and Millivolt meter. The system was designed around a Bearcat scanner. When Bearcat quit making the scanner, the system was redesigned from scratch and expanded to go to 1GHz, hence the SM-1000. If you look at the boards inside the SM-512 you will be able to identify the Bearcat model from the processor board. We made a bunch of neat stuff at Helper while Bill Detwiller (the owner) was still alive.
I will look to see if I still have a users manual for either of these still around. --- In Repeater-Builder@yahoogroups.com, "wb8art" <wb8...@...> wrote: > > Hi Mike, Best I can find out it is called a service monitor, hence SM > in model no.. Has Sinadder function as well as monitor RX and signal > generator and modulator, deviation, and off frequency detector meter. > > Randy > > --- In Repeater-Builder@yahoogroups.com, Mike Morris WA6ILQ > <wa6ilq@> wrote: > > > > At 04:06 PM 12/22/08, you wrote: > > >Anyone have a operations manual and or service manual for a Helper > > >Instruments SM-512 > > > > > >Randy > > > > Is that a Sinadder, an RG voltmeter, or another type of equipment? > > >
