[fields 100]

I wonder how the proper grounding effects operation of a radio.
For example, my 70 receives plenty with a 10ft of wire with no ground.On another hand, Atwater 84, which came with a 30 ft of old antenna wire will not accept anything shorter than that and only when I drop the first 10 ft on the ground and then raise it up.With all 30ft up it does not do as good. Now, if I ground the set, then it is completely different story-I can raise the entire 30 ft and it operates as great as my 70.
P.S.Both sets are aligned as per instructions.

[Mondial]

Most likely its because the Philco uses line caps while the AK does not. Since one side of the AC line ( neutral ) is connected to the house ground at the eleclrical panel, the Philco chassis is effectively grounded at RF through the line cap on the neutral side.

As far as the AK, it has no line caps but instead uses a interwinding shield between the primary and secondary of the power transformer. So the circuitry is isolated from ground and the set really needs an external ground connection for proper operation.

[fields 100]

Mondial,

Thanks, as always.

[morzh]

Or, you could possibly introduce line filter cap.

[gregb]

I have a 10 foot ground rod installed and that is the ground I use on my radios and it works fantastic compared to using the house electrical ground. I find I get noise with the house and like you describe it works with one and not the other. The ground rod works great with all my radios and really reduces the static and back ground noise levels.

Gregb

[fields 100]

Gregb,

That sounds good. How deep did you go? Are you saying you drove all that 10 feet down into the ground or just buried it below the surface?

[gregb]

It was a 10' ground rod and I drove it in till about 4" was still showing and attached my ground wire to it. Its on the north side of my house so shaded all the time and a little damp. I do water it from time to time if its really dry for any length of time to keep the ground damp.

Gregb

[morzh]

A properly set ground does not need watering.
Also rods used in reinforced concrete are not recommended for the job. Steel angles are the ones often used.

[gregb]

It the ground drys out I find the noise floor goes up. Where I live it is very dry and it doesn't hurt to keep the ground moist. You guys down in the north east would not have this issue ever.

Gregb

[morzh]

What kind of rod did you use?

[gregb]

It is steel with a copper jacket and I got it from one of the local electrical wholesalers. They come in 6', 8', 10', and 12' lengths at least that's what these guys had in stock.

Gregb

[Arran]

It depends on how the front end of the set is wired, in most sets the ground for the antenna coil is connected to the chassis ground or common negative, in some sets it's independently grounded. Also in some earlier set the volume control is in the antenna circuit so it will not function properly without an external ground.
I don't find that whether a set has a line capacitor or an electrostatic shield in the transformer makes much difference with the performance. Almost none of the Philcos had an electrostatic shield in the transformer, while all of the RCA and G.E sets I have did and having an external ground connected to the set did make much difference to either one other then cutting down on the noise. However on a Westinghouse 801 that I was working on the antenna coil was NOT grounded to the chassis and adding a ground improved the performance at least 30%
Regards
Arran