Simprop Scan 7
Simprop have been producing synthesised receivers for several years. For some reason they have had little exposure in this country and I am indebted to Dave Camp for introducing me to them. RCMW readers may have read his experiences in my Soarers Slot column (May 2004 issue).
The main advantage of a synth Rx is of course that it does not require a crystal, however the Scan 7 has some other interesting features as well:
- Optional extension cable for external scanning. (microswitch supplied, you provide the cable).
- Intelligent Pulse Decoding
- Voltage Monitor via high-intensity flashing LED
- Glitch and voltage drop logging, with interface to custom monitor.
For a full spec, I urge you to look at the instructions!
Re-tuning is easy enough - position the Rx near the Tx, press the Scan button on the side of the unit (or on the extension cable), hold and release. Scanning progress is displayed via a high intensity LED. Once scanning is completed, the frequency remains programmed into the unit even when switched off.
The LED also doubles as a battery voltage checker, by flashing at a rate depending on the voltage. A slow rate indicates low voltage.
Note that the specs say the unit supports channels 60 - 90, which would seem to indicate that 55 - 59 are not officially included.
The first unit I had did not have the IPD function working, but the second unit with revised firmware seemed a little better. However there is still too much jitter in the absence of a signal and during the scanning process.
I also did not like the flimsy case, just a thin sheet of polypropylene which does not offer much protection to the electrionics (the on-board microswitch on mine broke).
Scan Cable Gotchas
A couple of gotchas which are not explained in the instructions. Both to do with the scan button extension cable which allows the scan button to be places away from the body of the receiver, e.g. on the side of the model.
If you make an extension cable, then make sure you plug it into the DAT socket of the Rx the correct way round. Failure to insert the right way round will short the battery when you press the Scan button. If you do it long enough, wisps of smoke will thermal its way out of your model!! Been there done that, but too embarassed to get the T-shirt. Fortunately no apparent damage. However, Simprop really ought to make the Rx proof against this kind of error or at least to warn about it in very big letters.
Secondly, make sure you read and re-read the difference between 6 and 7-channel mode operation, as the synth cable extension depends on 6-channel mode operation to work.
In spite of the niggles mentioned above, the Scan 7 makes a reasonable receiver for sport flying gliders (I haven't tested it with an electric model). With the extension cable, it is possible to have a completely sealed radio compartment yet still change frequency.
Simprop products are distributed in the UK by J Perkins, however lack of availability caused me to get mine from Andy's Hobby shop in Germany which was considerably cheaper. German instructions were provided - no problem as the English ones are here. If you order from a continental supplier, remember to specify the UK 35 MHz band.
I am indebted to industry sleuth par excellence Dave Camp, for introducing me to these interesting receivers.
|Model||Simprop Scan 7|
|Channels||6, or 7 with Y cable|
|Op Mode||PPM / FM|
|Current Consumption||~ 20 mA|
|Dimensions||65 x 22.5 x 12 mm|
|Weight||18g (13g without case)|
|Channels||60 - 90 (UK)|
|Available From||J Perkins (UK distributor)
Andy's Hobby Shop, Germany