70MHz IF Receiver

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EM84tx
Original poster
Oct 19, 2012
96
43
Grand Haven, MI
I have a box someone gave me in the 80's or 90's along with a small dish. I remember him saying that it used a 70MHz IF. It is made by "New Electronics" kinda special. Either made for TVRO hobbyists or maybe for a radio station to get one channel ??
ON FRONT: it has a a signal meter, a variable knob with channels 1 thru 24 in a non-linear layout, controls for polarity, An (Audio) Wide/Narrow selection, a balance control etc.
ON BACK: an F connector IF Input, an F connector Receiver out (Channel 3?) RCA outputs LEFT, RIGHT etc

My QUESTION : Back when satellite receivers IF was near 70MHz... (And not L Band block like today) ----What did this thing do?---- I am guessing before BLOCK downconverters just LNA's So how did that work? I gotta look at this thing again. I am guessing it sent a DC tuning signal out to the LNA -Local Oscillator/mixer (at the dish) and the LNA always sent something back near 70MHz?

If there is a DC signal going back to the dish, what did it tweak? Did the LNA have dual conversion and maybe the tuning signal tweaked the FIRST IF? (70 MHz is pretty low compared to 4GHz)

So basically, what I have is a receiver that is stuck on ONE TV channel near 70MHz?
 
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I have a box someone gave me in the 80's or 90's along with a small dish. I remember him saying that it used a 70MHz IF. It is made by "New Electronics" kinda special. Either made for TVRO hobbyists or maybe for a radio station to get one channel ??
ON FRONT: it has a a signal meter, a variable knob with channels 1 thru 24 in a logarithmic layout, controls for polarity, An (Audio) Wide/Narrow selection, a balance control etc.
ON BACK: an F connector IF Input, an F connector Receiver out (Channel 3?) RCA outputs LEFT, RIGHT etc

My QUESTION : Back when satellite receivers IF was near 70MHz... (And not S Band block like today) ----What did this thing do?---- I am guessing before BLOCK downconverters just LNB's So how did that work? I gotta look at this thing again. I am guessing it sent a DC tuning signal out to the LNB -Local Oscillator/mixer (at the dish) and the LNB always sent something back near 70MHz?

If there is a DC signal going back to the dish, what did it tweak? Did the LNB have dual conversion and maybe the tuning signal tweaked the FIRST IF? (70 MHz is pretty low compared to 4GHz)

So basically, what I have is a receiver that is stuck on ONE TV channel near 70MHz?
My first receiver back in 1984 was like this. There was a separate Downconverter (NOT a block downconverter) module mounted right with the LNB's, and then the RG-6 going to the receiver. The downconverter used the LNB's high frequencies, and converted them to 70MHZ
 
I remembered something like this a 70 MHz IF was made by Swedish brand called DX for C-band a analog FM video mode back in the late 1980's.

It's comes with 24 channels up and down buttons with WFM and NFM dial going from 4.5 to 8.0 MHz ranges.

Same goes for wide and half bandwidth FM video when one C-band station is using half of transponder's space.😎

The C-band receiver's body was chocolate brown with red light channel number display.

I think DX receiver has a built in dish mover at that time with the 10 foot dish fiberglass, a heavy weight sized in the backyard!😁 :hatsoff
 
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