Loved my Regency TMR-8H (VHF 150-174 mHz, circa 1971) which used crystals ($5 each at the time) to determine which frequencies you wanted to monitor. I still have it and it still works great! Another classic in my collection is the Regency WHAMO-10 (model ACT-W10) with the very rare optional tuning box. This was the first synthesized Regency scanner which did not require crystals (circa 1974 or 1975). It used aluminum combs plugged into a diode matrix board on the back of the scanner to determine frequency. Teeth from the combs were broken off according to a frequency manual to determine what frequency was monitored. If the power failed, the memory could not be lost as was the case in other synthesized scanners of the day. This scanner had 10 channels. The optional tuning box, which is a very rare item today, had a bunch of diodes in it. You could plug this box into the back of the scanner and merely "dial up" the frequency you wanted to monitor for one of the 10 positions. You had the pruned combs plugged into the other 9 slots. The scanner itself and the optional frequency dial-up box were each the size of a shoe box. I still have this set-up which covers 30-50, 146-174, and 440-470 mHz. I wish I could find a cheap source of the aluminum tuning combs. I have seen them on ebay for $5 each and up, which is rediculous, in my opinion. In the mid-1970's, you could buy a pack of twenty from Regency for a couple bucks...
I also agree with the comments about the Pro-2004. I have had mine for nearly 20 years. It is a "classic".
