SLIDE'N

Back in the heyday of "CB radio" 23 channels were just not enough. With a busy Sunspot cycle driving DX you only had a short window to be able to talk across town with your friends, and that window-of-time lay somewhere after 3a.m. only to end about 3 hours later, returning to near full S-meter readouts with a wall of noise led by occasional voices from far away.

The 11m operator had few avenues in search of a quieter channel -

• Pony up big $$$ and buy a Browning or Tram, and operate off the VFO to slide in-between channels (Ch.3A was a popular hangout). This was a HUGE investment for anyone to undertake. A $700 expenditure in 1970 was equal to over $4500 in 2018.
• Take what was available within most radios by "Cutting-the-color-wire" on the channel selector. This gave you channels 22A and B.
• Find a compatible external VFO (Siltronix, PAL) for the radio being used and get the ability to slide in-between channels, not to mention below ch.1 or above ch.23.

Another approach to this was presented by HyGain in the form of their Hy-Range V (model 674) and Hy-Range VI, the matching VFO (model 675), pictured above. This presented the buyer with a matched pair of devices, both solid-state, allowing a person to listen to frequencies on-channel, in-between channel, and slightly above the 23 channel frequency.

Model 675 VFO ends some where above 27.400 MHz

The Hy-Gain "V" had several different releases, one with a dedicated VFO socket on the rear panel, and two without the socket. The 675 VFO could be hardwired into many other Hy-Gain radios and included the instructions on how to do it within the instruction manual which came with the unit.




BOTTOM OF 675 VFO

TOP VIEW OF 675 VFO PCB

While you will run across these on Ebay auctions or garage sales, the instructions on how to get this to work aren't so easy to find (read: VERY hard to find). Owners today are hard pressed to find anyone with the knowledge that these existed much less modified (still alive to talk about it). Every one wanted to know what to clip in the transceiver to allow Xmit when the VFO was plugged in.

But, what if the modification wasn't in the radio itself? Hmm...

In January of 1977, sales of 23 channel CB's were banned by the FCC in lieu of the new 40ch. PLL models, which were supposed to be harder to modify (I guess we know how THAT worked out. eh?)

The December prior to that had enormous discounts on 23ch. rigs! SSB transceivers which normally sold for $300-$400 were marked down below $50. Eventually entire inventories of new PCB’s found their way to the aftermarket for $5-$10, and Hams converted these to 10m fairly easily. There were quite a few articles in various magazines about how-to do the conversion. Hopefully they can still be found archived, and I believe that if you were so inclined to do something like this you would find it much easier to re-work a non-PLL CB to 10m vs. one w/PLL.

Today, with prices being what they are (Old CB's are now priced as "Classics", and Ham gear selling for good prices), a 10m conversion would only be good as a electronics project, and only if you had one stuck in a closet somewhere to experiment on.