Do tuners work better or sound better with a proper ground?

leesonic

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I was working on a tuner today, a NAD 4020A. It had the usual arrangement of a high value resistor connected between one side of the AC input and the chassis. I've come across this before in a Kenwood KT-7500.

Would these (or any other) tuners work and/or sound better with a 3-way cord with a proper ground? By work better, I mean would they pull in stations any better? Sounding better, I guess that is self explanatory.

A similar question would be, what happens if you connect the power the wrong way around? Presumably, you're meant to plug it in so the neutral side is connected to the chassis. But what if you connect the live (hot) side to the chassis? Not everybody knows (or cares) about the stripe on the power cable.

Lee.
 
OK I'll bite. In my experience AM radio reception gets much stronger with a good earth ground. By grounding the radio you're mimicking what happens at the transmitter. Current in the visible part of the antenna is reciprocated in the ground. So what you pick up in the air is relative to the ground and when you ground the radio you get the full effect. Kinda like the difference between doing pushups on a trampoline vs. doing them on the ground. More real work gets done with a solid ground reference.

Not the case with FM. The transmitted wave is completely formed by above-ground antenna elements. Grounding the FM coax shield does help to annihilate any crud picked up by the shield such as strong stations, other RF sources, etc. The electrical ground in house wiring is probably worthless on FM and might be a mixed bag on AM because it becomes part of the antenna circuit and may have a lot of crud on it that would interfere with your stations, even though the overall signal might be stronger.

So for RF ground use a cold water copper pipe that actually goes underground, or use those 8-ft grounding electrodes. I have no opinion on that resistor that you mentioned that connects the AC input to the chassis. That's some old school hardcore stuff.
 
Yeah, I figured it would be more beneficial for AM reception rather than FM. Thanks for your insight though.

If anything, a grounded chassis might help discharge the static build up I seem to accumulate, what with the heating drying out all the air in here.

Lee.
 
It can have some effect with line generated noise. The resistor to line is probably more for static buildup problems than anything reception related.
 
Your house ground can still have some resistance to ground which means that the noise elsewhere in your home electrical system can find a path into your ears.

Stuff like heater fans, light dimmers, fluorescent tubes, can make it not worthwhile. I did a separate ground rod for the coax lead from my antenna just avoid the house ground noise.
 
Hi with a question. Can I run a ground wire down to the ground rod used by our apt's electrical meters and use it instead of pound a new ground rod in? Thanks! AL
 
Don't see why not. Its much safer than having multiple un-bonded ground rods. Doing that invites very serious problems in the event of a lightning strike. Ground rods must be bonded with I believe #6 copper wire if you're doing multiples.
 
Thanks Gadget, hoping that will help when I hook up a long wire antenna to my 41 Zenith. Doesn't pull much in with the stock Wavemagnet ..
 
hm, those are usually pretty good unless a wire broke internally or something. Or unless the radio needs a little TLC. Often the IF strip gets off kilter on the older rigs and some re-touching can do wonders for them.

If you have a house like mine, they also are terrible. This place is all concrete block with aluminum siding. Its basically a faraday cage with extra shielding for good measure.
 
hm, those are usually pretty good unless a wire broke internally or something. Or unless the radio needs a little TLC. Often the IF strip gets off kilter on the older rigs and some re-touching can do wonders for them.

If you have a house like mine, they also are terrible. This place is all concrete block with aluminum siding. Its basically a faraday cage with extra shielding for good measure.

Thanks, will try the long wire and see if it helps, also the ground wire. If not then its a trip to Dave's. He re did my 3 Fishers and all is well with them.
 
Let me first preface my response by offering this being a licensed Amateur Radio Operator for almost 30 years and currently holding an Extra Class License (The Highest available) and being involved with electronics and especially stereo for years before that the simple answer a good earth ground will ALWAYS help and recommended in all installations.

AM being lower in frequency follows the curvature of the earth and also is more prone to noise and interference than FM. FM is more line of sight in propagation due to it being higher in frequency than AM.

The two broadcasts are different in nature. AM is Amplitude Modulation and FM is Frequency Modulation. In simple explanation FM is broadcast to a more limited audience area than AM which can be heard many times further depending on conditions.

The use of antenna types, coax(cable 300 OHM, 75OHM, etc. or commonly called feed line) also plays into the mix. The tuner is also dependent upon its ability to discern or separate signals and reject others to give you a final product. Some receivers work better and have more sensitivity, rejection, etc.

In short, the electrical ground of the unit is not the same as a separate earth ground which grounds the entire unit and the rest of the components inside to an earth ground and thereby helps dissipate static build up and also provides a path to ground of other RF coming into your receiver, in this case a tuner.

Depending on your location multi-path and other RF (Radio Frequency) is received along with your desired signals and the receive must be able to accept what signals it get, determine what to pass through and what to reject in order to deliver a signal or musical sound as a final result. Too little rejection and you get multiple signals and a bunch of different sounds, too much and some weak signals might not be able to be heard and you won't be able to tune in the station you want.

An outdoor antenna, proper feed line, even an external amplifier designed to limit the bandwidth of the FM broadcast to 87.1 - 107.9 MHZ is best. You may be able to use a simple dipole indoor antenna or you might have to use a more directional antenna such as a yagi (TV type ) or another design in order to pull in the signals with enough gain to be happy with the result.

All in all, this is a very brief post on the subject and it goes into much more depth than space allows or readers would care to read. So try this ground a stranded wire to the best point you can, keep the wire as short as possible as in don't run a 10 foot long wire in one run as it will act as an antenna and cause additional problems in some cases. Don't expect the "ground" plug to serve you as it will not do much with regard to eliminating noise or reception issues beyond a slight bit at best.

In closing I know people have opinions but this is proven factual methods and has worked from Hundreds of Thousands of Amateur and Professional Operations, engineers, etc., and I know it to be true as I have been doing this for over 40 years.

You can always check out the ARRL Handbook or search antennas if you need better reception or require more detailed info on grounding.

I hope this helps in a small way.
Hermit
 
Hermit, that was a great read and thanks. I have a Zenith 7S558 and hope to start listening to it again. Love DXing late at night although AM isnt what is was back in the 60's. Al
 
I was working on a tuner today, a NAD 4020A. It had the usual arrangement of a high value resistor connected between one side of the AC input and the chassis. I've come across this before in a Kenwood KT-7500.

Would these (or any other) tuners work and/or sound better with a 3-way cord with a proper ground? By work better, I mean would they pull in stations any better? Sounding better, I guess that is self explanatory.

A similar question would be, what happens if you connect the power the wrong way around? Presumably, you're meant to plug it in so the neutral side is connected to the chassis. But what if you connect the live (hot) side to the chassis? Not everybody knows (or cares) about the stripe on the power cable.

Lee.

After a lot of research, and speaking with an EE and electrician and antenna installer, I opted to put in three 8 foot grounding rods on two sides and one next to the electrical meter box on the house, the house is grounded to the water pipe. I ran a ring between all four grounding points. Both roof antennas are tied together and each on down one side of the house to a rod.

This was my best imitation of a commercial radio tower grounding white paper that I read.

I have zero noise issues or grounding issues of any kind, and my daughter volunteered that the TV picture looked better, it already looked great but it did somehow look better.

My understanding is that more grounding rods are better, but they have to be in a ring.
 
Don't stop there:

http://forums.qrz.com/archive/index.php/t-363766.html

https://www.google.com/search?q=tow...0CNLsoATX4oLABA&ved=0CB4QsAQ&biw=1360&bih=673

Just a few links on just grounding.

You should have been with us when we did the 400 footers and the salt basins with the 8 foot deep 2 foot wide salt rock and the 12" wide copper strapping to the bottom legs of the 160 meter tower vertical.

It can get absolutely insane on grounding an antenna/tower. I still have 2 55 foot motorized crank up to install along with my 4 element M2 dual driven 40 meter yagi and my 36 foot boomed KT-36XA Plus. the towers are rated 52 sq feet wind load @ 85 MPH and have the remote boxes to use as directional vertical arrays with the yagis serving as capacitance hats.

Bubo nice job on the grounding exercise but next time you go hunting for a balun contact this fellow:

Bob at Palomar Engineers in San Diego. I know this guy and he makes some of the best baluns money can buy. BTW a balun stands for Balanced to Unbalance and since you are using unbalanced cable RG6 Quad shield you would be best off having an antenna with a F connector or SO239 or even an N connector if it get down to it.

I run a 2 meter quagi from INNOVAntennas out of England and I think they make a version (commercial) for FM broadcast. These things are serious 2-3 inch 1/2 inch thick booms, solid 5/16 to 5/8 aluminum rod for elements. They are engineered to withstand ridiculous conditions, handle wind in excess of 100 MPH, just a BEAST.They are not cheap but they are the quietest antenna I have ever used.

M2 also makes some excellent antennas and if you hit them up they could possibly put something together specifically calibrated for the FM Broadcast band.

OF course you can make your own from some 2 inch thick walled PVC insert a dowel rod drill a few holes make a quad, yagi or quagi and have a nice antenna including hardware for under $100 or even less if you hit scrap yards.

A 8 element Quagi on a 10 foot boom would give you around 10-12 dB gain fairly easily and be a cinch to rotate with a light duty rotor. I have made 8 Bays or 8 Antennas stacked and coupled together for DX SSB work. Made my own frames, power dividers, couplers feed point harnesses and mounts.

If you check CL look for someone getting rid of a 2 meter beam and if in good shape just steel wool it, clean up the junction points, do the 1005/Frequency in MHZ and add a little stiff #4 or #2 wire to the elements then put it up. You could even find some aluminum tubing and just lengthen the elements a bit to obtain a good match. Even if you don't do anything else to modify the antenna you can still use it to some extent fro Broadcast FM, but a properly matched antenna will give you the best results.

Or go hunt down a VHF/UHF Yagi TV Antenna and use it for TV and FM with a splitter. Rat Shack is blowing these things out right now.

MFJ makes a cheap pre-amp and has kits that can work for FM broadcast range. Other companies do as well pricing varies so shop around.

Hermit
 
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