I have an old EMERSON model BL-210. After reading Angel-fire I re-read how to wind your own IF transformer & came up with a winding question.... The EMERSON does not have the original oscillator coil. The BL-210 also has a police band. The coil was replaced in the past, maybe it got damaged somehow (burned out) what ever. So someone put a duplicate coil in the set & ONLY the BC band can be received. Here's the question? How can a person wind a coil & put a tap in it? Is it hard or impossible to do? Would love to get this set back in some kind of newer shape so as to receive police calls. Which would be easier to do--wind a new correct coil or to add a second coil that would receive the police band? Also how can the correct location for the tap be determined & is there a SIMPLE way to find out? The BC band works "pretty much" OK(the dial calibration is "slightly off" but no big deal there. Riders shows a tapped coil, is there more or less wire on the police band because of the frequency difference? I hope someone can come up with a formula! The case is like new & the chassis is VERY clean! The EMERSON name is VERY plain & clear. The case is NOT broken or damaged in any way. In fact the case is in better shape than the chassis! (usually the other way around). Maybe someone could look at the RIDER schematic & find some "trick" that I can't see.

Putting in a center tap is not that difficult but you need to know how many windings to the point of the center tap. Then you would push the end of the wire through a hole on the coil form and pull it down through the inside of the coil form and tie it to your lug. This center tap wire would be doubled because you still have the main winding wire on the outside of the coil form to continue your main winding. You have just pulled the center tap without breaking the continuous winding. Make sense? Now as to how many turns?? Not a formula that I know. Think it is dependent on radio characteristics. Some of the old pros will chime in to clarify.

:Putting in a center tap is not that difficult but you need to know how many windings to the point of the center tap. Then you would push the end of the wire through a hole on the coil form and pull it down through the inside of the coil form and tie it to your lug. This center tap wire would be doubled because you still have the main winding wire on the outside of the coil form to continue your main winding. You have just pulled the center tap without breaking the continuous winding. Make sense? Now as to how many turns?? Not a formula that I know. Think it is dependent on radio characteristics. Some of the old pros will chime in to clarify.
: Be a lot of fun to hear from some of these "older" (please don't take this seriously) pros. I very much suspect that the people that designed these coils are NOT with us anymore. I (like a LOT of others) wish they were! A lot of our problems could be solved, & a much loved web site like this might not be needed. (Murphy's law says that there would ALWAYS be some innocent question) We miss these people very much-they contributed a HUGE amount to the wireless. They designed wireless things built like a battleship(brick shit-house). They were easy to fix & never seemed to fail!
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: I have an old EMERSON model BL-210. After reading Angel-fire I re-read how to wind your own IF transformer & came up with a winding question.... The EMERSON does not have the original oscillator coil. The BL-210 also has a police band. The coil was replaced in the past, maybe it got damaged somehow (burned out) what ever. So someone put a duplicate coil in the set & ONLY the BC band can be received. Here's the question? How can a person wind a coil & put a tap in it? Is it hard or impossible to do? Would love to get this set back in some kind of newer shape so as to receive police calls. Which would be easier to do--wind a new correct coil or to add a second coil that would receive the police band? Also how can the correct location for the tap be determined & is there a SIMPLE way to find out? The BC band works "pretty much" OK(the dial calibration is "slightly off" but no big deal there. Riders shows a tapped coil, is there more or less wire on the police band because of the frequency difference? I hope someone can come up with a formula! The case is like new & the chassis is VERY clean! The EMERSON name is VERY plain & clear. The case is NOT broken or damaged in any way. In fact the case is in better shape than the chassis! (usually the other way around). Maybe someone could look at the RIDER schematic & find some "trick" that I can't see.
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Please be aware that, even if you rewind the coil, you will not receive police calls on the old 'police band.' The upper end of the AM band was designated for police use in the old days, they broadcast on other frequencies today. The police band on an old radio will just pick up the upper end of the AM band, like above 1550kHz or so up to around 1700kHz.

"Police Band" is an imprecise description which meant different things to different radio manufacturers. For this model, the "Police Band" is really the range of frequencies from slightly below the top of the BC band (1580 KHz) all the way up to 4.2 MHz, or the lower shortwave bands. You won't hear any "police" traffic on this band but it isn't a totally dead range, either.