[Milsurplus] Solid state BC-611, GRC-9, BC-348 ?!

[ersmar at comcast.net]

Hue:

     I guess I don't use my Squad Radios enough (maybe once a year) to really feel the pinch from the lack of replacement tubes.  Actually, I have at least one spare for each radio I own so I can cannibalize the spare for parts for the operational unit.  Plus I've been able to find entire sets of pencil tubes for my PRC-6's and a few finals for my PRC-25, so I think I'm set, at least for this life.  

     Don't get me wrong - I appreciate the engineering that went into Craig's work and applaud his success.  And should I be fortunate enough in the future to own a good GRC-9 or two I certainly would consider his mods.  Sort of like mod'ing my Drake C-line station with parts from Sherwood Engineering.  Not from the factory, but improved equipment performance using SOTA devices.

    BTW - I'll likely be on 40M (7.250 or even 7.255 ECARS) Saturday morning through early afternoon with my single-band NVIS inverted V from Damascus, MD, located between DC and Frederick, MD.  If anyone hears me, please try calling.  

73 de
Gene Smar  AD3F


 -------------- Original message ----------------------
From: "Hue Miller" <kargo_cult at msn.com>
> >Gents:
> >
> >      To me, this approach kinda defeats the purpose of owning and 
> >restoring BA radios.  Having the battery-life problem is no different today 
> >than when the fully-tubed radios were first fielded and the GI's had to 
> >replace their batts every day or two.
> >
> >      However, I still want to give Craig (the developer of the schematics) 
> >credit for his innovation.  He certainly has reduced the current drain on 
> >the BAs' batts and improved the sets' performance with his SS approach.  
> >Congrats to him for this.
> >
> >73 de
> >Gene Smar  AD3F
> 
> I understand what you mean, and as i read his pages last nite, i was trying 
> to imagine
> what it would be like using such a solidstated set. It felt like maybe a 
> little less of the
> magic was there, a bit maybe.
> On the other hand, i have a number of sets and i find it a big hassle to 
> keep tubes
> stocked for all of them. When you get into exotic sets (such as foreign) the 
> hassle
> multiplies, plus the seller has you over a barrel and they know it. I really 
> resist
> paying $20 or so for a tube!
> Another thing i think about is, these tubes ain't being made any more, and 
> your
> precious tubes will eventually crap out, even the new ones, because the 
> glass is
> not 100% impermeable. Possibly we will pass from the scene before all the 
> tubes
> will, but be assured, tubes will one day be only "look at" items for 
> collectors. The
> only exceptions i can see is some tubes still kept in manufacture for the 
> tube
> audio cultists, tubes such as 6L6 and a few others.
> So maybe solid stating these sets is a way of long range thinking too.
> I was also thinking i'd let the fellow know that he might have experienced 
> better
> selectivity from the receivers if he had used MOSFETs instead. I think the 
> output
> impedance of the triode FET is just too low to do well with the IF tuned 
> circuits,
> which were probably dealing with about 1 M ohms plate impedance of the 
> tubes.
> / Hue Miller
> 
> 
> ______________________________________________________________
> Milsurplus mailing list
> Home: http://mailman.qth.net/mailman/listinfo/milsurplus
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:Milsurplus at mailman.qth.net