I now have a USA SD70 battery powered with the Aristo onboard mini receiver. I bought the receiver used and all it has for an antenna is a maybe 8 inch leangth of wire with a connector on the end where the person had it connected to the wheels and was using the track as an antenna. I have seen friends make up an antenna wrapped around a piece of cardboard and another way is just run the wire from a converted Aristo te track side unit installed in a box car or some other type of car with the antenna streached out the leangth of the car. What should the leangth of the antenna be and how is the best way to install it in an SD-70 for max reception? Wound up on a card or streached out or is there another way?
Terry Jackson
Make it about a meter long. It’s not terribly critical (Greg will correct me here.), but in general longer is better. 8 inches is rather short. At the Botanic, the static ones have been VERY extended above the roof of the building. One of the best installs I’ve done has it wrapped around a plastic card.
By all means wrap a 1 meter length wire around a card. It is MOST important to NOT have the wire cross over itself. The easiest way is to cut small V notches in the card and use them to anchor the wire in position.
Greg will not correct Tom as he is exactly correct…
You want the antenna near the length of the wave…
the formula is speed of light (feet per second) / frequency…
982,080,000 feet per second divided by 27,000,000 is about 36.37 feet…
for transmitting, you need to be full, half or quarter wave usually, for receiving a full wavelength or multiples is good…
So, back to what Tom said, the longer the better, and 8 inches compared to 36 feet is short…
It’s surprising how long the wavelength really is…
Regards, Greg
Terry.
If you want to maximise the range with a short wire you can always use one of the AZARR 27-Lite antennas. They have a total length of about 10" and work very well.
I’ve used the cardboard tube inside a roll of paper towels to wrap the antenna around. Works quite well.
I’ve also used hot glue to tack the antenna wire to the top of a boxcar I use as a battery car.
Got the sound going and the antenna extended with at least 39 inches wrapped around a plastic wire coil and wires not overlaping. Who much range should i expect with the Aristo mini onboard unit? I tried it and can have control about 6 ft away, but after that it loses control?
Hi Terry,
In your initial post you mention the wire which you thougt was originally connected to the wheels. I have an Aristocraft battery car and the short wire does in fact go to the wheels, via a brass bush with tag (inset into the axle housing) onto which the wire is soldered. This does make the track as part of the antenna system. I do not use the car at any time once track power is used.
Yes, that has been a common practice. Often works well. Ok, Greg, what does that do for your millimeter accuracy on antenna length
(http://www.outsidetrains.com/smile/mischief.gif)
(Still all teared up over “taking a Bruce.”)
