01-16-2006, 10:40 PM
The 37-10 used 9 tubes. The 37-11 is a 37-10 with the extra tube.
Generally speaking it was not just add a tube, but also changes in components, improvements to a part with a new part number, re-wire a circuit and/or eliminate a component(s), etc.
See this Service Tip from my site:
PHILCO SERVICE HINTS & TIPS - NUMBER 35
Philco Code and Run Numbers Explained
Production Change Notes were issued for these Code and Run Number changes. I provide these notes (when applicable) in the info packets I provide.
The 1938 Tube Manual I have on line only covers up through the 1938 models and may not reflect subsequent Run and Code changes in those models.
Generally speaking it was not just add a tube, but also changes in components, improvements to a part with a new part number, re-wire a circuit and/or eliminate a component(s), etc.
See this Service Tip from my site:
PHILCO SERVICE HINTS & TIPS - NUMBER 35
Philco Code and Run Numbers Explained
Production Change Notes were issued for these Code and Run Number changes. I provide these notes (when applicable) in the info packets I provide.
The 1938 Tube Manual I have on line only covers up through the 1938 models and may not reflect subsequent Run and Code changes in those models.
Chuck Schwark,
The Philco Repair Bench
[Image: http://www.philcorepairbench.com/images/philog3tiny.gif]
http://www.philcorepairbench.com
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
