Heathkit IM-4100 Digital Frequency Counter Powers On Ham Radio Test Gear

BK Precision 100MHz Frequency Counter 1803A

Vintage Digitron Frequency Counter 6550 USA - Untested As Is

Mercer Electronics Model 9800 Frequency 100 MHz Multifunction Counter

Simpson 710 frequency counter with power adapter 12751 and leather case 00747

BK Precision 1827 6 Digit , Autoranging Frequency Counter

Optoelectronics Micro Handi-Counter 3000A 10hz- 3ghz Dual Input

Heathkit IM-2400 digital frequency counter Untested