Blonder Tongue on channel 37

[lnx64]

I have a Blonder Tongue AM-60-550b, and it's maximum channel supported is 27.

However, I found by accident a little while ago, that channel 37 works too, and had less noise too!

Would it harm the modulator to go at that frequency if it's not supposed to be supported? I don't know if it drives it harder, or if it just gets sloppy on modulating. It looked fine though.

EDIT: Oh, this is UHF btw, not CATV.

[old_tv_nut]

Should not harm the modulator, but channel 37 is banned for broadcast use because it is used by radio astronomers. You should be nice and avoid it in case some university in your area is using this band.

[W3XWT]

Just don't run a test pattern for KLEE-TV in Houston on it...

[Sandy G]

Maybe whoever had yr Blonder/Tongue before you got it had done some "Twiddlin'" to it themselves..

[jr_tech]

Is there a list somewhere of the ranges of the various BT models? A number of different models show up on the 'bay and I am never sure of their capabilities.

jr

[lnx64]

Well the last part of the model, in my case, 550, is the max frequency it can do, which is UHF 27.

[lnx64]

Originally Posted by old_tv_nut

Should not harm the modulator, but channel 37 is banned for broadcast use because it is used by radio astronomers. You should be nice and avoid it in case some university in your area is using this band.

If terminated directly into my TV, shouldn't it not radiate that far outside of the house?

[old_tv_nut]

If connected directly, it should not be noisy on any channel - no need for 37.

Sent from my LS670 using Tapatalk 2

[lnx64]

It's really not noisy on any channel, but I like using the highest channel I can for things. Old habit. Like on every VCR, I used 4, not 3.

[W3XWT]

At least it's a Blonder-Tongue and not a Phasecom!

[lnx64]

I don't want to bring up a thread that's a few months old, but, on the blonder tongues, what's the offset dip switch for? The manual I got for it doesn't mention anything about this dip switch.

It didn't seem to make a difference when I toggled it.

[Jeffhs]

Originally Posted by old_tv_nut

Should not harm the modulator, but channel 37 is banned for broadcast use because it is used by radio astronomers. You should be nice and avoid it in case some university in your area is using this band.

Good grief. Whose idea was it to use a UHF television channel for radio astronomy? Every TV set with a UHF tuner can receive channel 37. There are other bands where frequencies could be reserved for this purpose. .... Oh well. The UHF TV spectrum is chopped up all to pieces anyway since the DTV transition, with only a handful of channels left for use by NTSC television stations in this country, so I guess the channel 37 issue may be a very moot point nowadays.

[jr_tech]

Ch 37 is used by radio astronomers for observations. Since they are measuring very weak signals, it is important that there are no transmissions (even part 15 is banned) on these frequencies (608-614 mHz).

Channel 37 is an unused television channel in countries using the M and N broadcast television system standards. Channel 37 occupies a band of UHF frequencies from 608 to 614 MHz, frequencies that are particularly important to radio astronomy because they allow observations at a frequency between the dedicated frequency allocations near 410 MHZ and 1400 MHZ. One radio astronomy application in this band is for Very-long-baseline interferometry. [1] In 1963, when there were very few stations in the UHF band, the US Federal Communications Commission (FCC) adopted a 10-year moratorium on any allocation of stations to Channel 37. A new ban on such stations took effect at the beginning of 1974, and was made permanent by a number of later FCC actions. As a result of this, and similar actions by the Canadian Radio-television and Telecommunications Commission, Channel 37 has never been used by any over-the-air television station in Canada or the United States.

from: http://en.wikipedia.org/wiki/Channel_37

jr