[Boatanchors] Re RME-69

[Richard Knoppow]

----- Original Message ----- 
From: "Phil" <dgnova at verizon.net>
To: <Boatanchors at mailman.qth.net>
Sent: Monday, February 27, 2012 12:20 PM
Subject: [Boatanchors] Re RME-69


> On the RME with the green dial:
>  Is there any chance you have a RME-70
> I have had both the 69 and the 70 at verious times. I 
> think the 70
> had octal tubes, and a green dial. Could be wrong. Going 
> by a bad memory.
> Reguarding  the dial ; the Hallicrafter dials, were
> made by a photographic process . The dials after a while
> turn brown. Did this happen to your RME ?
> Phil
>
     Do you mean that the dial markings are made by means of 
a photographic emulsion coated on the dial?  There are 
photo-based processes such as silk screening, which use ink 
to make the markings but are not actual photographic 
processes. If you have dials with a photographic emulsion 
which as become brown it may be possible to recover them by 
a bleaching process which is used on stained photographic 
negatives and prints. However, the dials on my old H 
receivers that have browned seem to be brown through out the 
dial, meaning the plastic itself has become stained. I do 
not know if a method for removing this stain or even if its 
possible to do. I think its due to a chemical change in the 
plastic but I am not an expert chemist so may be wrong about 
this.
    processes for recovering damaged photographic images are 
detailed in some handbooks.  The problem is that all entail 
a risk of destroying the image altogether. For photographs 
its recommended that duplicates be made either by means of a 
scanner or optically before applying any treatment. This is 
probably advisable for dials too. Some printers are equipped 
to print on odd sized materials such as making CD or DVD 
labels so perhaps could make radio dials. Its also possible 
to get ink sets for inkjet printers that are made with 
pigments rather than dyes and which have excellent archival 
properties including resistance to ultra-violet light and 
oxidation. There are also modern plastics which are highly 
resistant to breakdown and might be used for making new 
dials which would have very long lives. There is probably a 
way to adapt old dial hubs to new dials but it would 
probably require destroying the old dials.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com