[R-390] Ballast Tubes

[Rbethman]

Hello all!

    I bought my '67 EAC (R-390A) from an SK (WC3K) some three to four 
years ago.  In lieu of a ballast tube, it had the resistor in its place.

    I brought it home, plugged it in, turned it on.  It still is 
running, and running just fine.

Bob - N0DGN

Bob Camp wrote:

> Hi
>
> One thing you bring up that I should have mentioned. I have a couple 
> of radios that are running resistors and they seem to all work every 
> bit as well as the ones with ballast tubes in them.
>
>     Enjoy!
>
>         Bob Camp
>         KB8TQ
>
>
> On Jul 2, 2004, at 9:49 PM, Chuck Ochs wrote:
>
>> One must keep in mind that the R-390 was a "general purpose" 
>> receiver, which
>> saw extensive shipboard use by the Navy during it's heyday. Power aboard
>> ships tends to be anything but stable. I know. I was a shipboard 
>> electrician
>> on an LST during that nasty little war back in the sixties. We had these
>> radios on board, as did nearly every other ship in the Navy at that 
>> time.
>> Using a ballast tube in the oscillator filament circuits was, at the 
>> time, a
>> clever way to maintain stability during all those periods where the line
>> voltage sagged from operating such heavy electrical loads as gun 
>> turrets.
>> The regulation of ships generators of the period was very slow by 
>> today's
>> standards. IMHO, there is little ( probably NO) need for this regulation
>> scheme given a radio running on modern "shore power".
>> A few years ago, the ballast on my VERY early R-390 died, and I simply
>> replaced it with a resistor. I did not notice any change in operation
>> whatsoever. It has been running this way for several years now.
>> Chuck N1LNH
>>
<                      Bob Bethman - N0DGN
+-------------------------------+----------------------------------+
| N0DGN AMRadio Manassas, VA    |    REAL Tube Radio and AM        |
+-------------------------------+----------------------------------+
|       Manassas Radio - Home of Homemade Kielbasa & Pirogi        |
+-------------------------------+----------------------------------+
| Bob Bethman                \\\|///     " The absence of a danger |
| rbethman(at)comcast.net   \\ ~ ~ //      signal does *NOT* mean  |
|                           (/ @ @ /)      that everything is OK " |
+-------------------------oOOo-(_)-oOOo----------------------------+
|               <http://home.comcast.net/~rbethman>                |
| 1 BC-610I w/BC-614I,1 T-213/GRC-26 w/BC614I 1 '51 Collins R-390A |
| 1 '67 EAC R-390A, Heathkit DX-60, Apache, Mohawk, SX-101, HT-32A |
+------------------------------------------------------------------+
|           Amateur Astronomer - Celestron Nexstar 8               |
|             12" f5 Dob coming soon!  Being built                 |
|                  Meade ETX-60 (Got it back!)                     |
|               38 Deg 46.8' N - 77 Deg 28.5' W                    |
+------------------------------------------------------------------+
|   Opinions expressed are that of my own and do not necessarily   |
|         coincide with or represent those of ANYONE else          |
+------------------------------------------------------------------+
  ALL E-mail received and sent scanned by AVG & Norton Anti-Virus>