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Signal Amplifiers (Amps, Preamps, Distro Amps)

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#1 · (Edited)
This Preamplifier Comparison Chart was modified by holl_ands from an original chart at Solid Signal to show Max Input for two Strong Signals. It was reformatted into PDF form by stampeder with permission of holl_ands for the digitalhome.ca OTA Forum.

If you have any questions about the data in the chart please post in this thread.

Also see tczernec's Loss Calculator Spreadsheet in this post: http://www.digitalhome.ca/forum/showpost.php?p=877838&postcount=604. To use it, make sure to download it rather than using it online.

Another excellent tool is majortom's Cascaded Noise Figure Spreadsheet: http://spreadsheets.google.com/ccc?...rN2poRTVIalpwT3c&hl=en&authkey=CPbi9aYO#gid=1

Cheers
 

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#1,532 ·
When I contacted Research Commincations, I was concerned with using their 8 volt power supply because my coax run was almost 600 feet. I also asked why I couldn't use a locally sourced power supply instead of having one shipped here from England. I was worried there might be enough voltage drop to cause the amp not to work. That's when Ellen told me they use a higher 10 or 12 volt power supply for long runs - and anything up to 20 VDC would be OK. My question opened up that particular subject. I suppose they don't often get asked questions like that - but can't say for sure.

I get worried about voltage drops with all long wire runs - to the preamp or to the rotator. With rotators, I tend to use 14/2 UF direct-burial cable just to be safe, even though most rotators can be made to work with 18 gauge.
Note, I'm too cheap to buy 14/3 UF. 14/2 has a third uninsulated 14 gauge wire that gives me my third lead and works just fine.
 
#1,535 ·
Kitz Tests

I had a look at their website and was wondering which version you bought. I don't know if I'll need one yet as I'm still waiting on materials to build my M4, but I'm looking into amps just in case.
The website doesn't have much info on the coax version I was thinking might be good for me. If it does a good job, I'd get one instead of a CM7777 which I find a bit pricey. I like that it's adjustable. Do you use yours inside or outside? If outside, what enclosure are you using?

Marc
I have the new coax version of the Kitz Tech amp or pre-amp.

I did some basic test of the coax version and the results look like the same as the regular version.

Here's a test I did with the regular version :

http://www.digitalhome.ca/forum/showpost.php?p=956786&postcount=1132


But you have to take in consideration that the amps were tested with only one antenna (except CM7777) and if you put the Kitz after a UVSJ, you will get a small lost.

For the enclosure, I went to Addison, just minutes away from your location in walking distance, they have a weather proof enclosure for Five bucks.

At my location in Beloeil far from the big transmitters of Montréal, I find the CM7777 is the best for me.

I will do a full report of the new coax feed Kitz with a hacked 4221HD pointed at St. Albans for W52CD CH52.

Up to now, I find the Kitz to be good for connecting to one specialty or secondary antenna for trying to catch some low powered channel like W52CD or WVNY-DT.


My two cents,
 
#1,539 ·
I have the new coax version of the Kitz Tech amp or pre-amp.

I did some basic test of the coax version and the results look like the same as the regular version.

Here's a test I did with the regular version :

http://www.digitalhome.ca/forum/showpost.php?p=956786&postcount=1132


But you have to take in consideration that the amps were tested with only one antenna (except CM7777) and if you put the Kitz after a UVSJ, you will get a small lost.
Noted. But still, very impressive indeed.
For the enclosure, I went to Addison, just minutes away from your location in walking distance, they have a weather proof enclosure for Five bucks.
Yep, just down the street from here. I'm guessing you mean those gray electrical box enclosure (with the rubber sceal)?
I'll have a look at what they have next time.

I wanted more info about what was included with the coax version, and this is the email I got from Jeffrey at Kitz Technologies :

Q: There are no picture of the COAX model, can you supply pictures of the unit and what is included with this model? Do you include a power inserter module, or do I need a separate run of coax all the way to the unit?

A: We don't have a current picture of the COAX model yet.
This model comes with an amplifier, power inserter and power supply.
You do not need an extra coax for power.

:) Had to make sure, right? Figured I'd ask.

I bought/tested one of their original "indoor" units, and was amazed at how much it improved the analog signals I used it for. I also installed it briefly outdoors, high on my tower where the RC9260 normally resides. It was not as good as the RC there, but better than the CM 777x I had once tried.

Intravino later borrowed, and then bought, that unit from me, and I ended up replacing it with a second (bargain basement 3rd-hand) RC pre-amp. But I have since recommended the KitzTech to all comers, and some pals of mine have reported good success with it to date.
Thanks for the info intravino & mlord.
I'll wait till my M4 is up and running to see if I need additional boost.
Since I already ordered a 3414 for my setup, I'll wait and see if it helps.

Marc
 
#1,538 ·
Intravino's original unit (from me), unfortunately suffered an early death, but was replaced under warranty I believe.
Yes, that's 100 % correct. I asked Kitz to upgrade me to their coax powered version at the same time with a minor surcharge. He agreed (Kitz).

I just have to fully test it but it looks 100 % the same as the previous one.
 
#1,540 ·
Daemons,

Just keep in mind that mlord, and Intravino, are not in the same situation, location as us, on the island of Montreal,

generally, here in Montreal, I have found, so far, that the preamps do not help any.;).

I have tried the Kitztech, CM7777, Antra, GE, and CM3410 amps, none of which were impressive, still others did get improvements. It will ONLY depend on YOUR particular set-up, and location in the end. This basically calls for "trial & error" with the amps, and spending $ each time unless you can borrow. Returns are generally not accepted or not worth the trouble depending where you buy from.
 
#1,542 ·
generally, here in Montreal, I have found, so far, that the preamps do not help any.;).
On the island you will be very close to the analog transmitters on Mt. Royal and they can overload your pre-amp. I can't remember which ones are the worst offenders, but seem to remember reading that there are two that need to be notched out (I think one was 17 and the other was in the 30's). Also, unless the pre-amp has separate VHF and UHF amps, you will likely need to filter out VHF. All this should be done before the pre-amp.
 
#1,541 ·
#1,546 ·
If a VHF signal overloads (from a strong analog VHF broadcast), it can create harmonics that can interfere with UHF channels. Some pre-amps (such as the CM7777) overcome this by splitting the VHF and UHF, use separate amplifiers for each of them and then combine the bands together again. The band combiner will filter out the UHF harmonics from the VHF amplifier. If you don't care about VHF, you can filter out the VHF before the pre-amp if it uses the same amplifier for both.
 
#1,545 ·
Thats why I will wait and see if I need one or not. My being in the east end means I too am in a different situation than you are in. Different angle to different towers, etc.
The Kitz does offer a 10day return if not satisfied, so it's less risky.
Raybel in Montreal-East, do take back stuff but the box, instructions, bags and cables have to be in the same condition like when it came out of store.

I returned a eaves mounting system with no hassles but I was very careful with the bags and stuff.

Raybel have the CM 7777, CM 7778 and the Winegard amps.
 
#1,551 ·
Hi


I have a pa-18 uhf/vhf pre amp

It pulls in all the uhf channels nice with some ghosting ,
;;the antenna (DB-8) is at 5 feet beside my house , ( roofing it in the spring)

but my channel 13 analog is very wavvvvy and not soo clear.
11 is snow 6 is just noise ...
13 should be crystal clear---- like 14 , anyone have any idea on this..?

is the pa18 too much preamp ?
maybe the aforementioned vhf interference is evident here - how would I fix that ?

I want to have vhf and uhf
thanks
 
#1,554 · (Edited by Moderator)
hmmm well thats the thing

I have a hacked cm 4228 that when hooked up to the same pre amp brings in 13 crystal clear but 14 and up analog are all "fuzzy" like 13 is now and the cm 4228 is vhf hi ok and should be uhf analogue 14-69 ok

things are going on I don't understand

I can't get a v4 or a v10 in Canada for some reason ? maybe too high tech ? haha
 
#1,557 ·
Warning

Posts deleted and edited. The subject of this thread is Signal Amplifiers (Amps, Preamps, Distro Amps).

Please stay on topic.

As noted in our rules, If you wish to discuss where to buy products, where to get the best deal etc then please use the shopping forums.

This forum is for discussing the products features, specification and use.
 
#1,558 ·
Hi All:

Was considering which low-noise amp would be best for my situation (outside antenna), where my local transmitters (1 VHF-high on 7, all others UHF and a bunch of FMs) are all 8-11 miles from my house, and clustered together in the same direction where I'd need to point for receiving 2 VHF-highs on 11 and 13 and several UHFs about 65 miles away.

Seems that putting a low-side-terminated HLSJ in the line first would be a good idea, to get rid of the FMs first.

From what I've read here, the CM7777 would clearly be out due to overload likelihood, while the HDP-269 would seem to likely work fine (based on my reviews of others' similar situations). Wasn't sure how to properly read the stats to determine the overload stats for the coax-powered Kitztech KT-100VG-COAX and the RC 9261, compared to the HDP-269. If the stats were similar, would the fact that the Kitztech has variably adjustable amplification (while the HDP-269 and RC 9261 do not) make that the best choice for my area simply because I could adjust it just below the overload point if necessary?

Thanks in advance for your kind assistance...
 
#1,560 ·
marc, an A-B test is a good idea but I'm just mentioning that I don't think I've ever seen a mainstream Channel Master or Winegard amp or preamp malfunction on only certain channels - they either amplify the entire band for which they were designed or else they fail completely. Your situation is probably due to something else, but I don't mind being corrected if the preamp is behaving abnormally. My guess is that the tuner is auto-attenuating the strong signal, so you could even do an A-B test of tuners to add to your problem-solving.

Keep up the detective work. :)
 
#1,561 ·
Kitz Power Injector model

Hi,

I received lately some PM's about my test I promised to do with the new Kitz Tech pre-amplifier with power injector. I decided to share my results.
Compared to the old ampifier I got the same results with the new model.I tested the new Kitz my CM4221 and Archer pointed at Montréal and the tests are exaclty the same. With my 10y13s pointed for WVNY, it was the same results compared to the older model of Kitz Tech.

I'm using right now the Kitz with a Hacked 4221HD antenna pointed at St-Albans with an other LCD TV, no combiner and no splitter. Remember that you also need to make a box for the Kitz for weatherproofing. I was lucky to get great weather in late November for the installation on the roof.


I am planning to purchase a Winegard preamp in the spring of 2010 for my FM antenna and Sony HD radio. I didn't yet decide if I should buy a VHF preamp only (AP- 3700, 17 dB gain, 2.6 dB noise) or the more versatile VHF/UHF (AP-2870, 17/19 dB, 2.9 dB noise). I guess if I am not using the UHF input, I can always put a 75 ohms terminator on the UHF side. I emailed Winegard and they said the AP-3700 is superior for VHF only. Maybe they have a warehouse full of VHF only preamps because of the DTV transition and they want to get rid of them. If I get the VHF/UHF model, I can always compare it with the CM7777 and Kitz.

The VHF/UHF is more versatile for sure, as a backup also.

I need your comments and/or experiences with the Winegard preamps!


Intravino
 
#1,562 ·
Hi

I just got my Kitz tonight. I hooked it up in the basement replacing the pa18 pre amp on the antenna mast with a joiner. at 5 feet off the ground next to my house its no wonder install


Went inside powered up and voila channel 11 watchable !!! 6 watchable ! 13 great crystal clear none of these worked well before . Part of the reason was my db -8 none vhf hi antena -- but that means I can watch hi vhf now


The kitz warned not to play with the gain setting as the screw self destructs very fast so ok===== no touch set for hi gain.

yep I'm happy maybe when I roof the tenna in the spring it'll bring in pbs 23 hahahah :)


kitz thumbs up :cool:
 
#1,568 ·
id suggest NOT using a 4 way distro amp, especially if you dont need that, now a preamp is a different story, but even that in Montreal can be a problem!
My MythTV box has two seperate inputs for Analog and Digital, so I need an amplified splitter or else I'd lose all my signal in the splitter. But as others are saying, maybe I need to trap the FM. Especially in Montreal, we have stong FM towers (CKOI being by far the worst!).

Daemons, Are you using an FM trap prior to the input of the 3414? It can be a deal breaker even for UHF channels.

I find the 3414 very resistant to overload. Only 9 miles from the Wash DC towers using an FM trapped YA-1713, & pre-amped 91-XG (HDP-269) fed into a 3414 shows no signs of overload. Removing the FM trap is detrimental to most of the weaker stations 45 miles out; especially VHF. There is also an off-axis 160 kw UHF station only 2 miles away.
No FM trap, Antenna straight into the 3414. Now it makes sense that mostly ch22 would be affected. Theres probably a large harmonic from FM causing problems on that frequency.
If you are just using the UHF side of the UVSJ then you should be OK. A trap is only needed if you are inserting VHF with strong FM to the input of the amp.
I think I'll do that. I'll use two UVJS. One to remove the VHF to the amp, and the 2nd to combine the UHF/VHF back for my analog input. That way the amp will only see UHF.

Mlord: Do you think Active Surplus still have those UVJS you mentioned in the splitters thread? I know it was some months ago, but I might want to try them now. :)

Marc
 
#1,566 ·
FM Trap with drop amp

Hmmm..., this is interesting. Are you saying a FM trap is recommended to use before the CM 3414 drop amp? I am 2.5 miles from a TV tower that probably has FM signals coming off it (it's the CHCH tower in Hamilton). I am currently using a UVSJ splitter to help attenuate 11.0 which comes off this tower- this has helped a little- now if I add an FM trap, maybe this would help too- which FM trap is recommended?
 
#1,569 ·
Yes, Active Surplus still has more than 100 of those UVSJs in the box down near floor level. I picked up another handful of them this past weekend. :)

Are you sure that you "need" that distribution amp, now that there's a good pre-amp in the system? A pre-amp normally replaces any need for distribution amps.

I can split the output of my pre-amp here 8-ways without having our weakest digital station (very weak) drop out from the HVR-950Q tuner. A 16-way split kills it, though.

On the other hand, the digital input to the HVR-1600 tuner doesn't seem to tolerate anything more than a 2-way split for it's weakest (local) station. So for that, I used an asymmetric 3-way splitter, putting the HVR-1600 digital onto the strong output leg, and then using the two weaker outputs for our analog tuners.

Cheers
 
#1,570 ·
Yes, Active Surplus still has more than 100 of those UVSJs in the box down near floor level. I picked up another handful of them this past weekend. :)
Great. I'll give them a call today. Might as well order a few to make up for shipping.
Are you sure that you "need" that distribution amp, now that there's a good pre-amp in the system? A pre-amp normally replaces any need for distribution amps.
I don't have any pre-amp in the system. This 3414 is all I have atm.
On the other hand, the digital input to the HVR-1600 tuner doesn't seem to tolerate anything more than a 2-way split for it's weakest (local) station. So for that, I used an asymmetric 3-way splitter, putting the HVR-1600 digital onto the strong output leg, and then using the two weaker outputs for our analog tuners.
The HVR-1600 is a pita. It's because of it I got this 3414 in the first place.
That, and I was planning down the line to add a HVR-2250 to my MythTV box.
I'll try with the UVJS in the mix first before buying another (pre)amp. I would need them with a Kitztech preamp anyhow, right?

Marc
 
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