View Single Post
Old 27-Nov-2020, 5:03 PM   #84
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
Quote:
Originally Posted by tripelo View Post
Wonder how you use the BT double sideband Modulator?

Do you inject a tone to provide a pair of CW signals, or add a DTV baseband. or something else?


My use is very simple. I don't have a UHF signal generator, so I use the NTSC video carrier of the modulator as a constant strength test signal. All I have to do is select an output channel on the Agile Modulator and tune my signal level meter or SDR to that frequency. It isn't necessary to modulate the carrier, the video carrier exists without video or audio input.



For VHF, I use a more sophisticated (and expensive) source; I generate an ATSC 1.0 carrier with my Thor Petit Modulator.







Testing the Thor Petit HDMI RF MODULATOR
https://www.avsforum.com/threads/tes...lator.3095882/
Attached Images
File Type: jpg CH40ModulatorCalib3_1.jpg (203.4 KB, 3526 views)
File Type: jpg Blonder Tongue HAVM-1UA_2.jpg (73.9 KB, 3548 views)
File Type: jpg Thor Petit HDMI RF Modulator1_2.jpg (110.9 KB, 3542 views)
File Type: jpg Thor Petit HDMI RF MODULATOR2_2.jpg (68.4 KB, 3539 views)
File Type: jpg Thor Petit HDMI RF MODULATOR3_2.jpg (76.9 KB, 3377 views)
__________________
If you can not measure it, you can not improve it.
Lord Kelvin, 1883
http://www.megalithia.com/elect/aeri...ttpoorman.html

Last edited by rabbit73; 27-Nov-2020 at 10:21 PM.
rabbit73 is offline   Reply With Quote