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Full Version: Model 90 Tube Shield
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I’m considering buying a Model 90 cathedral that is missing the large 3-tube tube shield. Philco made three versions of this model with different output tubes (early w/ two 45s; mid w/ one 47; and late w/ two 47s). “My” radio is the mid version. Does anyone know if the large tube shields for these three models are interchangeable? The early and mid versions appear to have the same tubes and tube layout for the tubes in the large tube shield (24, 27 and 24). The late version appears to have different tubes and a different tube layout. Therefore, perhaps the early and mid versions are interchangeable.

Additionally, the radio has a vertical bracket on the opposite side between the rectifier (80) and output tube (47). You can see the bracket in this video (5 minutes into video): http://www.youtube.com/watch?v=ptQ2d0VsZmc Does anyone know the purpose of this bracket? Another tube shield?

Thanks!
Hi Allen

Sorry for not replying sooner.

The large tube shields for the early (2-45) and mid (1-47) are interchangeable; the shield for the late version (2-47) is different and is not interchangeable with the early and mid versions - but the third version shield is interchangeable with Model 91.

Yes, the flat metal in the mid version is another tube shield; it serves mainly to protect the two 27 tubes in the audio circuit from interfering with one another, I believe. In early versions of the "mid" chassis, there was a single round shield over the 27 tube that is next to the 47 output tube. This was later changed to the flat shield which is missing in your set.
Hello Ron:

Thanks for your reply. Using your information, I found photos on ebay of several Model 90’s with both tube shields. Now I know what I’m looking for should I decide to purchase the radio. I'll try to attach the photos for reference.

I appreciate your time and assistance.

Allen



Note from site admin: Sorry, but the photos which were attached to this post are no longer available.