The two UHF inputs would likely work to stack two antennas. Antenna models, direction and cable lengths must be identical to work properly. Stacking can increase signal strength and reliability if done correctly.
This is a known problem all the way back to the RCA PREAMP1R dual input model.Hello Folks,
I recently picked up an RCA TVPRAMP12E (single input) Kijiji purchase - "brand new in box" to experiment with and compare to my CM7777. Unfortunately, this has defective a power inserter (no load voltage = 8.95 V). Preamp won't power up at all (blocks all signal when installed). I changedout the wall wart (hunch), which made no difference. It's likely the VR, which on the later models looks to have changed to a CJ7809 chip. The circuitry has changed from previous version shown on this forum and the AVS forum reference data. There appears to no longer be a diode on the i/p to the VR chip.It appears to have been replaced with a choke??? View attachment 11675 View attachment 11674 Pics attached. Has anyone come up with a solution for failed power inserters for these preamps (other than return)?I was thinking of using a spare unregulated inserter I have kicking around, and using a resistor array to drop the voltage down inot the 10.5VDC range. Maybe not enough regulation for the preamp with that option. I can't return it as it is a Kijiji buy.
My soldering skills are ok, but these micro components make changout quite difficult.
Thanks and cheers....
Thanks.....I have searched but haven't found any solutions.This is a known problem all the way back to the RCA PREAMP1R dual input model.
It's been well-documented by others on this and other forums. I believe somebody had a cure for it but it might take a while to do some digging.
Thanks for the reply/info. I checked the drop box links, they are no longer active. I opened up the preamp itself, just to check for bad/cold solder joints but didn't see anything.When I first got the first one I ever had in 2013, I measured 95 mA drawn from 9.4 VDC output from the insertor.
I had tried to rig it up so I could eliminate the wall wart and let my antenna rotor's regulated supply power it up instead.
I no longer have them here (gave em away), since as I mentioned in that post, it wasn't able to be run off of the DC power supplied by my Antenna Rotor.I suspect that it will do as well as or slightly better than the RCA. It's a tiny bit quieter (0-.75 dB) on UHF and a little bit (5-6 dB) more robust on overload tolerance. Of course, it's my conclusion that the "1 dB of noise claim" missed the mark.www.digitalhome.ca
An Avant X would be a better solution for that scenario, allowing you to filter individual UHF multiplexes from each antenna.This summer I installed a Televes 536081 mast mount pre amp and like it so far. It has a single VHF input plus 2 UHF inputs. I tried to run 2 separate UHF antennas(pointed at different cities) into it to avoid a rotor but got lots of interference and went back to single UHF and single VHF antennas. Nice to get American stations in London Ontario even this late into fall. When American channels went thru reassigning frequencies I lost most of my USA channels but this pre amp helped get some back.
The main advantage of the Juice preamp is its ability to withstand overload better than most other preamps. This is shown by a higher IP3, MAX Input Signal, and SFDR. The high SFDR (Spurious-Free Dynamic Range) allows it to handle strong local signals without damaging the weakest desired signals.What do people think of the Winegard LNA-200 Boost XT vs. the Antennas Direct Clearstream Juice? The Winegard is roughly half the cost, but I'm willing to pay the extra $ if it buys a significant increase in performance.
The best preamp for any location depends upon the desired signals at that location.
Understood, but I am currently getting 34 channels with the above rig, so whether through good planning (I did spend a while calculating angles and cable lengths while designing that stack) or good luck, I seem to have a workable setup.I wouldn't combine the two antennas. It will potentially introduce significant amounts of multipath and interference, especially on weak signals