[GreenKeys] Western Union Comment

[Jim Cooper]

On 25 Apr 2019 at 3:02, JC White wrote:

> Were those machines popular in the 60s?

As I recall a few hams tried to use them 
with tones over VHF without a lot of success ... 
plus they were actually rather messy and 
smelly -- the basic function was 'blasting away' 
the Teledeltos paper (lots of paper dust) with 
an electrical spark (lots of ozone in the air).