[R-390] What's in the window?

[rbethman]

*All,

*Here is a "copy of the extensive info":  (The area is bounded by ** at 
the beginning and ** at the end.)

Quite clearly---> ** aftermarket 8 ohm audio stagenestled in the space 
next to the PTO**

<http://cgi.ebay.com/Late-model-EAC-Collins-R-390A-R390A-R-390-/280589662946?pt=LH_DefaultDomain_0&hash=item4154727ae2>

I find all the totally off the wall "answers" ludicrous.  YMMV

Bob - N0DGN

> Thisreceiver, EAC Serial #2844, is apparentlyone of the latest ones, 
> as shown by the October 1967 date stamp in the photos.  It  has the 
> latest updates, including the IF module filter trimmers and the 
> desirable Cosmos PTO with a wide end point adjustment.
>
> It is typical mil-spec, usingmodular construction, coil forms 
> impregnated with Araldit, and teflon wire insulation. As shown in the 
> photos, the engraved front panel and original knobs and meters appear 
> practically new.   The gearing is tight, yet free, showing little, if 
> any wear. All controls are smooth and effective, and all filters and 
> bands function as they should.  This late model  receiver is a hot 
> performer, perhaps owing to the extra care taken in its overhaul.
>
> For example, not only were weak tubes replaced, but also low noise JAN 
> tubes were installed in the RF, mixer, and first IF. Alignment was 
> done a second timeafter a month's burn-in.
>
> In addition to the usual cleaning, lubing, and shaft alignment, tuning 
> lightness and smoothness were further enhanced by deburring and mesh 
> adjustmentof right angle display drive gear teeth, and resetting the 
> typically over-stiff anti-backlash spring tension in the KC shaft 
> drive gear. Meters were disassembled to adjust movement bearings often 
> overtightened at the factory.  Noise was reduced and signal input 
> increased by using a toroidal balunto get proper antenna balance and 
> correct match to the receiver's balanced 150 ohms,  instead of the 
> typical practice of feeding one side with 50 ohms through a nice 
> looking adapter.
>
> For longer tube life, two CL 80 thermistors were added to control 
> filament stressing inrush. A 44 ohm resistor ballast was installed to 
> save unnecessary wear on the3TF7 ballast tube, (which is also 
> included). After cleaning and mechanical alignment the controls, gears 
> and slug racks were lubricated with Bel Ray synthetic aviation oil 
> (some single malt Scotches cost less)
>
> While an overhaul such as this goes far beyond the norm, this receiver 
> is also far beyond the norm.
>
> Classified Top Secret until 1967, the R-390A is considered by some to 
> still be the best HF receiver ever designed.  Stories are told that 
> R390A's are still in use by the NSA, where senior operators far prefer 
> their quietness over modern, mega-dollar receivers from Harris, Racal 
> and Watkins-Johnsonwith their noisy synthesizers and digital filters.
>
> New R-390A receivers built in 1968 (the year following this one) were 
> briefly sold to the public for $1700, which would equal $11,000 today.
>
> <Included in the sale are are the ballast tube, all 3 covers, and the 
> antenna matching toroid.In addition, a compact HiFi speaker is 
> included to go with the ** aftermarket 8 ohm audio stagenestled in the 
> space next to the PTO**. (shown in the photos).>
>
> Shipping includes professional packing and insurance.    Fedex ground 
> seems to have the best track record,  but I'm open to suggestions.  
> Local pick up is preferred.  As with all electronics, no returns.  
> Ships to USA only.
>