High Def Forum - Your High Definition Community & High Definition Resource

High Def Forum - Your High Definition Community & High Definition Resource (http://www.highdefforum.com/index.php)
-   Local HDTV Info and Reception (http://www.highdefforum.com/local-hdtv-info-reception-9/)
-   -   RCA TVPRAMP1R Amplifier (http://www.highdefforum.com/local-hdtv-info-reception/141993-rca-tvpramp1r-amplifier.html)

Pete Higgins 08-07-2013 08:12 PM

RCA TVPRAMP1R Amplifier
 
IDRick, Tigerbangs & All,

I want to report my findings with my new RCA TVPRAMP1R Amplifier. This looks like one of the few remaining switchable dual VHF/UHF input, mast mounted, pre-amps. with a switchable FM trap. I got mine for $22.80 delivered from NothingButSoftware.com, but they are available through Walmart for $21.95, Office Depot for $22.99 and Solid Signal for $27.99 plus $4.95 shipping.

Manufacturer (for RCA) is VOXX International
RCA literature says :”Outperforms old preamps made for analog & preserves signal purity with Extremely Low Noise (ELN) circuitry” but doesn’t specify an actual NF. Other features listed include:
Separate or combined inputs for UHF/VHF (switchable)
Switchable FM trap reduces interference from FM frequencies

Before I ordered it I contacted Audiovox Electronics (the company who makes them for RCA) and requested its specifications. I received the following information in an email.

From Audiovox Electronics:
The TVPRAMP1R is spec at: 16dB gain with a 2dB noise figure and 22dB gain with a 3dB noise figure.

Thank you for using Audiovox Electronics


A follow up email indicated they did not have any more data available.

A technician @ Antennas Direct who goes by “ADTech” on the digital home web site had previously characterized this model around Christmas time and shared what he found on that forum. He has access to some pretty impressive HP test equipment for characterizing preamps. including an HP8569B Spectrum Analyzer & an HP 8970A Noise Figure Meter.

Here is what he found for the RCA TVPRAMP1R:
Low VHF - 3.9 dB NF/16 dB gain
High VHF - 3.1 dB NF/16.2 dB gain
UHF - 2.6 dB NF/23.7 dB gain


I wasn’t bothered that the RCA didn’t quite live up to its published specifications. On the contrary, it came much closer than others –some of which I own.

He also provided his sweep data of the FM Trap which I plotted. He used an HP 8970A that makes simultaneous noise figure and gain measurements. 5 data points were missing due to an 8970A annoyance in its data output where if the measured NF exceeds its self-calibrated max input (usually between 30 and 35 dB NF), it outputs a standard "garbage" value for both NF and gain that has to be ignored. Rather than substitute “filler” values, I chose to ignore the missing data. His data indicate a double notch filter offset to prevent channel six attenuation.

http://www.highdefforum.com/members/...ca-fm-band.jpg

The supplied power brick is hard wired to the power inserter and is rated @ 12 VDC, 200 ma. Mine actually outputs 16.63 VDC. Output from the power inserter measured 9.50 VDC unloaded and 9.47 VDC with the amplifier connected. This is important to know because unlike my Winegard amps that have the voltage regulation in the mast head unit the RCA amp. has the regulation in the power inserter. For long cable runs or if you decide to use a different power supply/inserter you will need to insure 9-10 volts is delivered to the amp. I took mine apart to compare it to both of my Winegard preamps.

http://www.highdefforum.com/members/...mplifier-1.jpg

http://www.highdefforum.com/members/...mplifier-3.jpg

I probably wouldn’t have bought the RCA TVPRAMP1R Amplifier if ADTech hadn’t indicated they bench checked pretty good (compared to other preamps. he’s tested), well that and the fact that it only cost $22.80 delivered. I owe him a debt of gratitude for all the work he’s done and for sharing his data.

I connected my new RCA TVPRAMP1R Amplifier to my HDB8X & YA 1713 to give it a try. Voltage at the amplifier input measured 9.50 volts through 50’ of solid copper RG-6. I had it set for dual VHF/UHF inputs with the FM trap switched in. I wanted to first try it without the Antennas Direct FM band pass filter and the Channel Plus NF-471 channel 24-29 filter that I have to use to keep my Winegard AP-2870 from overloading to see how badly the new RCA overloaded. Boy was I surprised. It didn’t show any signs of overload!

The NF-471 is designed to remove RF channels 24-29 but rolls off slow enough that at my location it also removes channel 30 (KPBS, 15.1 @ -96.3 dBm from San Diego) and channel 31 (KTLA, 5.1 @ -103.5 dBm from LA) plus channel 32 (KDOC, 56.1 @ -110.9 dBm from LA). So by just swapping out the AP-2870 with its required filtering I added channel 24 (KBEH, 63.1 @ -98.6 dBm from LA), channel 26 (KVCR, @ -15.60 dBm from Box Springs Mtn.), channel 30 (KPBS, 15.1 @ -96.3 dBm from San Diego) and channel 31 (KTLA, 5.1 @ -103.5 dBm from LA) plus channel 32 (KDOC, 56.1 @ -110.9 dBm from LA). Not sure why I couldn’t get channel 29 (KFTR, 46.1 @ -107.4) but it wasn’t there with my 91XG/PCT MA2-M combination either.

I should probably be shot for what I tried next, but I pointed my CM-4228 towards LA and combined its output with the HDB8X and applied that to the UHF input. This should give me a further boost in signal strength probably >1dB & <3 db. While I can’t quantify how much of a boost in signal strength this gave me, it wasn’t enough to put the RCA into overload. Based on a sample size of one, and some less than scientific testing I conclude that the RCA TVPRAMP1R Amplifier is way more overload resistant than my Winegard AP-2870 and possibly even my single input Winegard HDP-269. The HDP-269 is specified for high signal environments but last year when I had mine connected to my 91XG/Y10 7-13 through a UVSJ it was overloading, which is why I switched that array over to PCT MA2-M drop amps.

Finally, I disconnected the dual UHF antenna configuration and connected just my CM-4228 to the RCA’s UHF input. Subjectively, I couldn’t tell any difference between the two UHF antennas when used with the RCA preamplifier.

I did feel like, on a channel-by-channel basis, my SNR’s were higher than with the AP-2870. Again, that’s very subjective and could be nothing more than propagation. Dealing with predominately 1-Edge & 2-Edge signals I experience a lot of day-to-day and even hour by hour variation in signal quality.

The signals that I suspect overload both of my Winegard amps. are an FM station KOLA on 99.9 MHz @ -13.4 dBm and KVCR on RF channel 26 @ -15.6 dBm. Both stations are on Box Springs Mtn. ~ 3.5 miles from my back door. To make matters worse, I have to point my antennas right at them to get the LA stations.

Based on one day of testing, I think this is a quality product that has shown good tolerance to overload. Here is a link to my TV Fool report so you can see the type of signal environment I’m faced with.
http://www.tvfool.com/?option=com_wr...1dda169109ca5c


hoopitup2000 08-08-2013 04:44 AM

Nice work Pete.:) Good to see there is an excellent low cost alternative to the underwhelming Winegard amps in mixed weak/signal environments.

IDRick 08-08-2013 08:20 AM

+1 Awesome work and excellent write up! Thanks for sharing the info Pete, very useful and helpful!

ImRizzo 08-08-2013 10:08 AM

Well done, Kudos for your time and effort, much appreciated.

vulcan141 09-12-2013 10:15 PM

rca preamp
 
thanks pete for the info...i ordered mine and now i need to ask you an installation question...i have a db4e from solid signal that in having intermittent reception on vhf channel12.
i now have my db4e connected with a 3' jumper to a straight thru ground block with the block connected to a ground rod with aluminum wire.and out the other side to my tv.all is well except the intermittent vhf.
now to install my rca it shows it connected directly to the antenna and out the combo uhf/vhf to my tv.my question is can i run the rca from under antenna thru ground block and then to indoor power supply and to tv without losing anything in the process.
thanks in advance

Pete Higgins 09-13-2013 04:37 PM

vulcan141,

I really don’t use ground blocks. Where I live in Southern California, we rarely get rain let alone lightening. I don’t think I’ve seen lightening in the area in the 32 years I’ve lived in this house.

As I understand it, a ground block is no different than an F-81 female-to-female splice with the addition of a facility to attach a ground wire and perhaps a mounting frame or a mast clamp. As such it should have no effect on your signals other than the small amount of insertion loss introduced by the F-81 and the two cable ‘F’ connectors. I doubt if your intermittent reception on vhf channel 12 is related to or caused by the use of the ground block since I would expect a feed-line intermittent to be noticed on all channels. The ground block will pass DC to the amplifier.

As far as I know, the db4e is a UHF only antenna so you may need a VHF antenna with more response to channel 12. If it is weak signal, adding the RCA TVPRAMP1R Amplifier may overcome enough distribution loss for it to break clear. The proof will be in trying.

Since you are interested in getting channel 12 and only have one antenna, I would configure the RCA for a single input (i.e. for a combination VHF/UHF rather than separate antennas) and connect the db4e to the UHF (dual) input with a short coax jumper. Connect the amplifiers output to your grounding block and the other side of the grounding block to the cable that goes into your house and the power inserter. The reason you want the amplifier as close as is practical to the antenna and ahead of the ground block is so that you are leveraging the amplifiers gain to overcome all the distribution losses possible. You can hook the amplifier anywhere in the chain between the antenna and the power inserter but the further away from the antenna it is, the less benefit you derive.

So I think the short answer to your question is YES. Let us know how things work out.

IDRick 09-14-2013 12:20 PM

Just wanted to give a quick update. My Winegard AP8700 pre-amp had failed after 4 years of service. The cost to replace the power brick and power inserter was the same as buying a new RCA pre-amp so I opted for new. Installed it today and found I had lost a channel. Turns out on of our local stations had gone off the air a few months ago and I hadn't noticed... Oops! The RCA works well, has a great price and an easy install! :-)

Pete Higgins 09-14-2013 03:56 PM

IDRick,

I have a similar situation. TVFool lists 11 LOS channels in green & yellow for my location but I only ever get KVCR, the top one & KVMD RF channel 23 (31.1 - .10) the 5th one down. The second one down KILA-LP on RF channel 8 (51.1) is supposedly LOS, on Box Springs 3.1 miles from my house but, in over a year, I’ve never received it. Same goes for the rest of the green & yellow ones listed. The majority of what I get is all the 1 & 2 Edge listed in the red and grey part of the table.

I don’t know how much tinkering you like to do but if you think the problem is in the power brick or inserter you may be able to get your AP-8700 up & running to keep as a spare. If it’s like my AP-2870 & HDP-269 it will have an 8 VDC voltage regulator on the amplifier circuit board. (I’ve read that it does.)

My Winegard AP2870 & HDP-269 both came with the same power adapters P/N 2780230 rated @ 120 VAC 60 Hz 14W input & 22 VDC, 0.4 amp. output. Mine actually measure 33.5 VDC output (unloaded). They also came with a PI-1000VR voltage regulated power inserter that takes the 33.5 VDC input and regulates it down to 17.43 VDC output that goes into the coax to the amp.

You could probably feed your AP-8700 with any voltage between ~10.5 & 20 and not tell any difference (i.e. the amplifier circuit board only see’s 8V regardless what you feed it). Just make sure you wire it with the coax center conductor positive. It’s most likely the power brick that burned out in which case you could even use the power inserter over.

If you have a volt meter the transformers are easy to test with just a piece of coax with an extra ¼ or ½” center conductor sticking out one end. I made up several just for that purpose. If it’s the Winegard power inserter substituting a generic one should be ok, depending on how high the output is from your power brick.

The power bricks that came with my PCT drop amps. are P/N A-P/A-1260315U and are rated @ 120 VAC 60 Hz 100 mA input & 15 VDC 250 mA output. They actually measure from a low of 17.3 VDC to in excess of 24 VDC (unloaded), and use an ‘F’ connector output. One of these would work with your Winegard power inserter or any aftermarket power inserter. I would be happy to send you one if you need it.

Glad my input finally helped you, I kind of owed you from when I was starting.

IDRick 09-14-2013 07:40 PM

:hithere: Pete! I appreciate the pre-amp recommendation and the advice for setting up a spare. I didn't spend any time diagnosing the issue on the AP8700, the light was off on the power inserter and I lost several channels. Enough wrong to order a new one (I wanted one with dual inputs anyway...). :yippee: We're getting ready for a remodel project which impacts my shop area... Most of my tools etc are boxed up and moved, will take a bit to find the voltmeter... I'll get back to you! Thanks again for advice and take care my friend! :)

trosti 09-17-2013 07:19 AM

RCA TVPRAMP1R Amplifier
 
Well, I guess in the end you pay for what you get. I've had the RCA TVPRAMP1R preamp mast mounted using both the UHF and VHF inputs for about 3 weeks. I have a winegard VHF and the HDB8X UHF antenna combined on the preamp. Yesterday I noticed all VHF channels were gone. I went up on the roof and my guess was correct the preamp lost VHF for some reason. Luckily, I had a VHF/UHF combiner which I connected my UHF/VHF antennas into. The downlead from that is now fed into the preamp but I had to switch it to UHF/VHF combined setting. Everything now works again and seems to be ok. I'm not sure of there is any more loss from this setup. Anyways, I guess my point it buyer beware since it seems to perform well but maybe isn't built all that well. What can you expect for 20$ that performs as well as some more expensive pre-amps.

Pete Higgins 09-17-2013 11:41 AM

trosti,

I am sorry to hear you had problems with your RCA amp. I have purchased 4 and the first two and the fourth are working perfectly. The third one I tried didn’t work for VHF either. I found that by not moving the combined/separate switch all the way to the end of its separate travel the amplifier worked as expected. Fortunately, the switch has enough friction to hold its position when it’s not at the end of its travel. I have been using it for about a month that way and so far all is well.

Audiovox warranties these amps for 12 months against defects in material or workmanship, but you have to pay the return shipping. Since I need at least two units configured for separate inputs I plan to eventually just remove the switch and install jumpers for the separate position. I have a vacuum operated de-soldering station so I know that isn’t a practical solution for everybody.

As far as the additional loss, there will be additional insertion loss from the combiner and the extra piece of coax from the combiner to the amp. It should be negligible probably .5 to 1.5 dB, depending on components used.

If all is working well for you it probably isn’t worth going back up on the roof to try playing with the switch. If you do, please let us know if that solved your problem. Audiovox may have installed a quantity of defective switches.

IDRick 09-17-2013 04:14 PM

Pete, I also had a problem with the combined/separate switch during my installation. I tested the amp in my tv room and my sole VHF channel came in fine. According to the manual, the default setting is combined (which is what I needed). I then installed up in the attic and assumed all was well. The next time I tried accessing ch 8 (ABC), it would not come in. I went back in the attic and found that the combined/separate switch had moved over to a separate setting. Adjusting back to the combined setting lead to full reception of ch 8. Clearly the switch moved on its own from my office to the attic install. We'll see if it stays in place after the install and readjustment...

Pete Higgins 09-17-2013 07:46 PM

IDRick,

Like I mentioned above, I have three that work fine but one with the VHF issue. I should probably get up on the roof and get it down, pull the switch, and see if I can figure out what’s going on. It’s almost like at the end of its travel its opening the VHF path (UHF continued to work on mine). As you know, my signals are way too weak to couple across.

I won’t be able to do anything for a while. Tomorrow, I have a cleaning crew coming to clean one of my rental houses and Thursday I have movers meeting me in Victorville to move my wife’s son into it. This is the same one we evicted 6 months ago from the condo I bought for him. –Don’t Ask!

If the dust settles by next week, maybe I’ll be able to report something. One of the guys I used to fly with and his wife wants to get together with Karen & I this weekend for an out of town dinner and my High School class is having a 70th birthday party on the 28th so my dance card is filling up. I figure as long as I’m still burning oxygen I may as well go for it.

I’ll post back if I figure anything out.

trosti 09-18-2013 02:41 PM

As always thanks for your time Pete..I'm happy with using the combiner before the preamp and keeping the switch on the combo setting. It seems to work great. My setup has been wonderful so far besides this huccup. Things should only get better in New England as the leaves start to fall off the trees. If I have any other issues with the preamp I will prob mount my old RadioShack amp up

Pete Higgins 05-06-2014 05:39 PM

Defective RCA TVPRAMP1R & comparison with Winegards LNA-200 Boost XT
 
1 Attachment(s)
Defective RCA TVPRAMP1R

Recently I started noticing what looked like a jamming signal corrupting my Tower’s high VHF & UHF TV channels. Regardless of the displayed SNR my Hauppauge Digital Signal Quality (CX24227) meter would max out the red “Correctable Errors” & “Uncorrectable Errors” bars. However, when I switched over to my HDB8-X/LNA-200 system, the interference cleared up.

Yesterday I replaced the Tower’s TVPRAMP1R with the LNA-200 and reception was fine. I reinstalled the TVPRAMP1R and the problem returned. In fact if I tuned in a weak FM station I could hear the noise burst for 1-2 seconds and then 1-2 seconds of no noise then the burst would return. I had a spare TVPRAMP1R so I installed it and operation returned to normal although it seemed like the new TVPRAMP1R was working better than the LNA-200.

Since it was still under warranty I boxed up the defective unit and shipped it back to Audiovox in Hauppauge, NY. It cost $14.93 to return so I’m not sure I wouldn’t have been smarter to buy another new one for $22.80 and keep the power supply & U bolt as spares?

While I had stuff apart, I decided to run a signal comparison between the newly installed RCA TVPRAMP1R and my Winegard LNA-200.

The tower test array is as follows:

Antenna Craft Y10-7-13 Yagi @ 42’ AGL w/40’ RG-6
Qty. 2 Antennas Direct 91XG’s (booms separated 23” with the top one 46” below the Y10-7-13)
Each 91XG is also connected through length matched 40’ RG-6 cables and connected together with the same type of UHF combiner used with the HDB8-X 8-Bay Bow Tie.

RCA TVPRAMP1R was set for separate inputs FM Trap enabled. The Y10-7-13 40’ RG-6 was connected directly to the VHF input. The HDB8-X UHF combiner was connected to the UHF input with an F-71 M-M coupler.

For the LNA-200 test the Y10-7-13 & HDB8-X UHF combiner were connected through a Steren 201-604 UVSJ to the LNA-200, again with an F-71.

As the graphic below portrays, the RCA TVPRAMP1R boosted the signal by approximately 4 dB more than the Winegard LNA-200 Boost XT.
http://www.highdefforum.com/members/...6-may-2014.jpg
The Blue trace displays the RCA TVPRAMP1R performance the Green trace displays the Winegard LNA-200 Boost XT performance and the Red trace displays the difference in signal strength {RCA ~ 4 dB stronger}.


All times are GMT -6. The time now is 02:34 PM.

Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0
Copyright ©2004 - 2008, High Def Forum