[Boatanchors] RCA Marine Receivers

[Al Klase]

Richard,

I do have a Radiomarine AR-8511 that was designed primarily for crew 
entertainment.  Runs on 115 VCD, and has six 35L6 tubes in 
push-pull-parallel to get the required audio output for multiple 
speakers from low B+.
Read about it on page 22 here: 
https://worldradiohistory.com/Archive-Radio-Age/Radio-Age-1945-July.pdf

Al

ARK Sig Block Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net/
On 5/28/2022 1:37 AM, Richard Knoppow wrote:
> RCA made two late marine receivers, the CRM R6A and a shipboard (DC) 
> version, the AR 8516. These are nearly identical but use different 
> tubes so that the AR-8516 can have series heaters on a 110V DC mains 
> supply. It has two more tubes in its tube count, haven't figured out 
> which ones yet. I have neither of these receivers but am curious about 
> them. One big question is the specs. The image rejection for both 
> receivers is the same and not very good. At 30Mhz its listed as 30db. 
> That would be acceptable for a single conversion receiver with a 
> single RF stage and 455Khz IF but not for a double RF stage even if 
> single conversion and this is a double conversion receiver. In 
> comparison the RCA AR-88 is speced (and performs) with an image 
> rejection of 200 at 30Mhz, which translates to 46db. This is very good 
> for a single conversion receiver but how could a deluxe receiver of 
> twenty years later be so much worse. So, the question occurs to me is 
> the spec for the R6C really that bad. I have none to test and am not 
> likely to ever get one so I wonder if anyone has experience with them 
> and has ever tested the image rejection. A bit of a puzzle.