[BC] Collins exciter

[Dave Hultsman]

Wonder if it was the original fan or even a factory specified replacement fan?   Many of those exciters are still in operation and we stock most of the parts for them including fans.   I have argued with the Collins and Continental engineers about an air interlock for fan failure.  They said the interlock switch would about the same amount of trouble as the fan. On the later model Exciters a temperature sensor was on the PA which would reduce power or shut the PA off if it over heated.
 
My experience in the field is that many contractors, upon loosing a fan located a similar fan locally, to the one used in the exciter.  I have seen some of those lose bearings and self destruct, since they were not designed for continuous duty.  Then instead of ordering the exact replacement from CEC or Newark, the non standard fan was left in until it self destructed again.  I have seen those exciter operating with the fan completely clogged with dirt.  Once cleaned up the vanes and restarted they ran well but the station's engineer ordered a replacment.
 
Also remember all moving parts usually will fail.  Ideally any station should have either a replacement motor or fan assembly on hand for a transmitter final PA stage and especially for the FM Exciter. It is a shame to be off the air with a 25 kW. FM because of no exciter blower spare on site.
 
The same would go for the Collins, Continental, Broadcast Electronics  and many other FM Exciters with blowers.  It's not if its when!!!!
 
 message dated 2/6/2012 9:40:04 P.M. Central Standard Time, ebukont at msn.com writes:
>Ever seen one of those exciters self destruct?  I got a call one cold dark snowy morning....