Crystals
RC Crystals
RC Crystals usually come in pairs including one Tx for the Transmitter and one Rx for the receiver. The majority of crystals in the rc world will be on a single conversion setup with exception to the high end radio sets which will be on a dual conversion frequency instead. Brands such as HSP / ACME / BSD / HPI and many more will use radios on a single conversion frequency.
What is the difference between single and dual conversion?
Simply put dual conversion is much more sensitive and more selective with regards to its frequency numbers in comparison to single conversion and so they can not be mixed for this reason. This is due to dual conversion receivers converting the incoming frequency into a lower frequency twice (where as single conversion would only do this once), conversion is done due to circuit boards working much better at a lower frequency. Dual conversion will generally be much more expensive kits and the crystals will be marked as so. So simply put if your crystal does not say either then you will usually have a single conversion setup
In RC these 4 bands are the most commonly used for rc crystals:
27mhz AM Crystals Receiver and Transmitter (click here to view range)
27mhz FM Crystals Receiver and Transmitter (click here to view range)
35mhz FM Crystals Receiver and Transmitter (click here to view range)
40mhz FM Crystals Receiver and Transmitter (click here to view range)
Crystals we stock come in pairs, one for the transmitter and one for the receiver.
72mhz is not legal in the UK.
Will these rc crystals work with my RC and Receiver?
To find out remove your previous transmitter rc crystal.
Their usually will be something along the lines of 27.045 AM written on it.
The first two digits is the important part as it represents (for example) 27mhz.
The last two letters (after the number) represent the band your RC is on.
The last 3 digits can be different to what you have already but the other parts must remain the same.
Most rc crystals with 27mhz AM written on it will fit that particular radio and receiver.
I removed the sticker and found a different number on the silver crystal case to my transmitter crystal case?
Receiver crystals will have a lower number than the transmitter crystal. This is due to the transmitter sending on one frequency and the receiver receiving on another. However to help avoid any confusion with regards to pairing manufacturers will mark the stickers the same number.
Channel numbers and colours appear to be different to my old set of crystals?
Manufacturers tend to change the rc and receiver crystal sticker colour to them own colour scheme. If your looking for a specific crystal always go by the number and dont use the channel number or crystal colour as a reference. This is especially important if your using your model in a rc club.
Where else can it be found?
If not written on the rc crystal itself then it could be found:
- on a sticker along the bottom of the RC
- or on a small round sticker on the receiver box lid
- or finally in the manual.
Can I use two models on 27mhz AM at the same time without them interfering?
Yes if the last 3 digits are different, for example 27.045 and 27.095 will work together without interfering, however two rcs on 27.095 wont.
