I know we covered this before somewhere else . Any Ideas.

If the signal goes down in strength when you touch the rod, this is normal with a ferrite rod antenna.
With a ferrite rod antenna it would need front end alignment if touching it improved the signal.
If its a standard aerial coil, with wire aerial, sounds like a problem in that area.
More info needed on your particular circumstance/model/aerial/lenght?
But most sets I come across can always do with touch(correct procedure) of front end alignment.
The correct procedure is what catches many out, with many just tweaking trimmers for loudest signal.
Which then ruins performance further up or down the band.
Try and follow manufacturers methods for the model being aligned.
JJ

It's my 1934 EMMCO. It has the same circuit as the 1938 Weldon 3/38 on page 306 of the 1938 AORSM.
The aerial length was only about two meters. A length of wire hung on the ceiling.
Plus non of the resistors have been checked or replaced. so I will do that on the weekend.

These sets were intended to be used with an outside antenna. i.e. 100ft plus.
Or even longer. broadcast band one wavelength equals 200 Meters.
So you are likely to get very mixed results with a couple of meters.
I'm not sure if your radios RF coupling coil is adjustable.
Will look at circuit if theres one.
JJ

Standard length for most was 25 feet. There is such a thing as too long. RCA put out a chart in the 30's showing this. I have a copy & it is also floating around on the WEB.

By touching the antenna post you are not only placing a resistance to ground on it, you are likely upsetting the trim. I normally set the aerial trimmer last with a long wire antenna attached, never with a signal generator attached (fault excepted).

Marc

RCA put out a chart in the 30's showing this

Here: http://www.nostalgiaair.org/Resources/download.asp?FN=\M0015412.pdf

The chart does not show broadcast band wavelength.
An old rule of thumb was that the minimum wire antenna length should be 1/8th of a wavelength.
So, broadcast band would be 25 metres(approximately 75 feet).
This rule however is probably aimed at transmitters.But would equally apply.
Over my years of servicing the norm was a couple of feet draped down the back of the radio.
My comments to these owners was "Its like owning a Mercedes Benz and running it on kerosene!"
JJ

I am going to be building a antenna in the next few weeks so I will try the 25 metres . I have all the gear just not the time to do it. So I will give it a burl. My son is here visiting so he can give me a hand.

I have not done much with an antenna yet since moving house, but the temp one is around 20 metres.

I could get 2CH easily at night on the previous EW antenna on the workshop (520km) it was around 20m.

The one I used on the Comms receiver, with antenna matching, was 50m.

Marc

Signal fading when I touch antenna. Any Ideas.

It could be that the aerial coil is wired in reverse. Try swapping the earth and aerial connections on the primary of the coil.

If there is no sign of tampering on all of the antenna coils terminals I doubt that it is the cause. As far as I am concerned the problem is load: The finger taking signal to ground.

Poor signal induction is normally the result of adjustment, an inferior antenna and poor RF ground return. There is a practice with American "Hot chasses" to put a cap from Neutral to chassis, to provide an RF path. Rather a nasty compromise as their two pin plugs can be reversed, assuming they were wired properly in the first place: Don't do it.

Rather an unsavoury practice; With a transformer set it is desirable to fit a cable with earth: That is a much safer option, if it has not got one. Do try grounding it to see if that improves things, if its not grounded and keep fingers off the input.

It is also desirable to adjust the antenna trimmer/s on the weakest signal in the area of 1500kHz you can hear, with a decent antenna, or the one it is to run on, fitted.

Well it is actually plugged into the isolation transformer. Its on my work bench so I am thinking that may be the issue. I will be building a proper antenna this week.