Thread: 91XG or DB8e
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Old 12-Aug-2017, 12:50 AM   #20
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
Quote:
Originally Posted by welkin View Post
Is there a unit you recommend besides the RCA
The RCA TVPRAMP1R Preamp is inexpensive, works fairly well, but does have quality control problems. In particular, when using separate UHF and VHF antennas, the switch must be set to SEPARATE. In that position, it sometimes makes poor contact with the VHF antenna. The fix is to use COMBINED and an external UVSJ ahead of the preamp input. Also, people that buy an Amazon warehouse special, often get a return that doesn't work because the power supply/power inserter hasn't be checked.

At first I was puzzled by ADTech not suggesting the Juice preamp which is made by the company he works for. The Juice has a low noise figure (good) and is resistant to overload. My guess is that the power supply would need to be custom to power two preamps through one coax. Their power inserter would handle the current for two, but the power supply might not. The PCT SMPS512UTRH for the second generation 7777 might work:



I favor the two coax and combine after the two power inserters approach, because it avoids the power supply problem and allows you to test each antenna system separately.

Also, there is the FM interference problem. The Juice does not have an FM filter and you have a strong local FM transmitter that might cause a problem with VHF reception. I did an FM signal report based on your TVFOOL report, but it isn't accurate enough because you are so close to KMYK:
http://www.fmfool.com/modeling/tmp/5...3/Radar-FM.png

Can you please do an exact address FM signal report so that I can see how close my estimate was:
http://www.fmfool.com/index.php?opti...pper&Itemid=29

Any maybe while you are at it, a more recent TVFOOL report (which will still probably have some errors because the tvfool database isn't up to date):
http://www.tvfool.com/index.php?opti...pper&Itemid=29
Attached Images
File Type: jpg PCT SMPS512UTRH.JPG (117.0 KB, 3319 views)
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Last edited by rabbit73; 12-Aug-2017 at 12:57 AM.
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