YET406PC telescopic antenna replacement

HI. New here, so please be gentle. I have purchased some YET406PC remotes. They have that YUCKKKKY telescopic antenna. I would like to replace it, but am having difficulty. Frequency is 315 MHz, so I have tried making some 23.8 cm long wire wound antennas. I used 0.83mm insulated copper wire, wrapped around a drill shank so that external diameter is the same as the pull out thingie. I positioned the new antenna so that it was inside the plastic enclosure of the TX hand-piece. It works great up close, but fails after moving out to about 7-8 metres. I have tested the old pull out antenna on the same system and I am able to get about 80-85 metres. My question is, what makes these telescopic antennas different? I have to be doing something wrong, yes? Thanks in eager anticipation

Hello Colin,

Telescopic antenna shouldn’t be that different, I think you can absolutely replace it with your copper wire, but you will need to keep it straight just same as the old telescopic antenna, please try and let me know the results.

Hi William, thanks for the reply. The reason that I am replacing the telescopic antenna is to 1. reduce the height of it and 2. save having to pull the thing out in the first place. I thought that coiling the wire would serve to intensify the field strength. Is this not so? If not, do you believe that there are any options? I need to have a transmit distance of about 50 - 60 metres. Thanks again.

Can you please take a photo showing the board & your new antenna, upload at then post the image address here? I will check if I can help.

Hi William, done. I have uploaded 2 remotes. One uses a 315MHz stub that I bought. To fit, part of the board was removed. This included some of the antenna plane track. What I did was connect the tail, which was the same length as the removed track, to the point indicated on the top remote. The length that is on the under side of the board is un-braided, but insulated by heat shrink.

I guess that this is the address.

Bugger, just noted that I said SMB joiner. It is SMA mail-mail. The co-axe tail has had the facets filed off to mike it fit easier. BTW, all swarf was removed from the connector

Sorry for the late reply, I just got answer from engineer.

Typically helical antenna like yours will have less power gain than the 1/4 wavelength whip antenna, and another factor might be impedance mismatch and frequency deviation, in which case you will need to modify on board matching capacitor’s value.

Since you will need to know how strong the antenna strength you get during adjusting, you will need to have some kind of equipment such as spectrum analyzer, or you can try some low cost SDR software defined radio hardware, like this

  • You can choose other SDR solutions, the above link is just provided for convenience, we are not affiliated with the seller in any way, and can’t guarantee the product’s function or quality.

Another easier way would be changing your receiver module, by change your existing one to better superheterodyne receiver with good sensitivity, maybe you can get 50 - 60 meters distance under current antenna configuration.

Hi William, thanks. That was pretty much what I thought. Changing the receiver is going to be difficult as there are interfaces to consider. I have spoken to contacts in China and they are looking into removing the telescopic antenna and incorporating a stub. Will have to wait and see what happens there. I don’t have a spec-an, but will look at the link, thanks. I guess that I will just keep plugging away at it. Thanks again for your assistance.