[QuadList] save htis and look tr4 converts to hi band but alsoneed modul...

[Dale Lamm]

Just catching up on posts. Did not mean to imply that adding a hi-band head to a lo-band machine would constitute the complete conversion, it's just one step. However, doing this on a TR-5 did make the editors more pleased with the quality of video brought back from remotes.

Hi-banding was an expensive operation for a small station in the 70's. We had moderate success hi-banding (playback only!) a couple well-used TR-22's by following a homebrew procedure given to us by some helpful folks at a Kaiser Broadcasting station in Detroit, where the non-RCA conversion was probably designed. Widening out the bandwidth of the RF stages was a big part of the process.

One safety note for anyone working on a TR-5. The deck will raise up about 10 inches in the back, making it easier to slap those heavy 60 min reels of tape on the machine. There is a potential guillotine hazard if fingers get caught between the underside of the raised deck and the machine's side panels; and the deck drops unexpectedly. A single pair of telescoping square metal tubes with a pushbutton latch are all that supports the raised deck. I drilled a hole in the lower tube and put a #10 bolt through it whenever the deck was raised, which was 95% of the time.

The machine in the color photo looks very clean, like it had seldom been on the road. Just hook the video out to an old monochrome Conrac monitor with a decent sync separator and playback will be fine for a museum. Consider showing off the unit with monochrome video in LBM mode, to get away from the fuzzy appearance of color, due to the lesser-deviated LBC mode and dot-crawl issues.

[snip]

FIG. 2. All of these transistorized TV tape recorders include
new circuits needed for high-band operation. For TR-22's, high
band is a third mode of operation which can be added to
monochrome and color modes already built-in. For the TR-3,
TR-4, and TR-5 the high-band mode can be selected as a
second mode of operation.

[end]
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