[TenTec] Omni VII filters

[Dr. Gerald N. Johnson]

On Fri, 2006-08-04 at 07:12 -0400, Carter, K8VT wrote:
> So, the Omni VII preliminary specs say "Collins mechanical filters"...
> 
> Now, back in the day, I was a Drake man, not too much into Collins. 
> However, I vaguely remember reading something about mechanical filters 
> not being the best under QRN conditions. (subject to ringing or some 
> type of distortion???)

S-line vintage Collins filters were bad about ringing. The IF output
connector showed a continuous envelope from line noise. They turn static
clicks to lengthy crashes.

The rounded shoulders inherent in the ladder filters used for a long
time in analogue Tentecs don't ring much. Lightning still sounds like
clicks.

> 
> Any comments on mechanical filters vs crystal filters?? Any problems 
> with mechanicals and QRN , or is my memory failing me (again)?  :-)

The new Collins mechanical filter for CW in my FT-857D doesn't seem to
ring nearly as much as the SSB filter did in my 75S-3B.
> 
> Inquiring minds want to know...
> 
> 73,
> Carter K8VT

-- 
73, Jerry, K0CQ,
All content copyright Dr. Gerald N. Johnson, electrical engineer