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When is a GEM not a GEM?
Posted: 25 Apr 2024, 16:52
by stuart mackay
Question for those of a certain age, did the aluminium folded cased GEM single channel and 4 channel radios marketed by Keil Kraft have any connection with the plastic cased Mainstream GEM 1+1 and the exquisite (1) GEM 4??
Re: When is a GEM not a GEM?
Posted: 25 Apr 2024, 17:28
by leccyflyer
Hi Stuart
The Gem in your first picture was a bit ahead of my time I think. The Gem 1+1 transmitter in your second picture is identical to the one that Shaun and Phil kindly passed on for me to fly my Outlaw last year, which I understand came originally from Wayne. I'm certain that those transmitters were produced by the same folks as that beautiful Gem 4 set, used by the young guys who were my inspiration for trying radio control in the first place and sold by Roland Scotts in Walkden, on the East Lancs Road.
My original GEM 1+1 had a more rectangular folded metal case and a different stick than the one in your picture - looking much more like a Waltron 2 transmitter, in fact identical, other than the GEM logo in that Space 1999 style font.
Re: When is a GEM not a GEM?
Posted: 25 Apr 2024, 20:39
by RON
Here’s a GEM single channel I made a few years back. Using Phil’s pic encoder.

- IMG_2201.jpeg (90.58 KiB) Viewed 1870 times
Re: When is a GEM not a GEM?
Posted: 25 Apr 2024, 21:02
by Phil_G
My recollection is that all Gems were badged Mainstream though I may be wrong on that.
For most Gem sets you can find an identical Mainsteam equivalent in a different colour.
The bog-seat Gem is a peculiarity, you wonder if that particular set was made specifically for Gem at an unfeasibly low price by
a company who would normally be churning out little toys to be used in Christmas crackers.
But no, it was Mainstream - they were masters of injection moulding. I had a bog-seat for one weekend, from Roland Scott,
when we took it back the guy said " throw it on the pile over there with the others"...
it was replaced with a DigiAce which I still fly to this day. But having said that I wouldnt mind doing a bog-seat conversion now, just for devilment

Cheers
Phil
Re: When is a GEM not a GEM?
Posted: 25 Apr 2024, 22:19
by Mike_K
I think Mainstream and GEM were both brand names of F&J distributors. Mainstream originally made Simprop sets under licence in the UK, then brought out GEM as their budget range. They were supplied with GEM labelled Simprop servos. I think Shaun has a metal cased GEM with Bonner joysticks and I have a metal cased GEM with SLM joysticks. The Tx and Rx circuit board layouts and components are very similar to a Simprop Alpha.
Then they brought out the toilet seat GEM 4, with F&J (Europe) Distributors on the GEM 4 instructions and box. It was completely different circuit design to previous GEM 4, the previous ones were good quality, a complete contrast to the toilet seat. It was still supplied with Simprop servos. I've no idea if the toilet seat was designed by Mainstream or if it was made by others and just "badge engineered" GEM 4..
Re: When is a GEM not a GEM?
Posted: 26 Apr 2024, 13:23
by Shaun
Here's my proper Gem tx.
If Bonner sticks weren't so dire, I could have been tempted to 2.4 it.
Re: When is a GEM not a GEM?
Posted: 26 Apr 2024, 17:29
by Pchristy
Nothing wrong with Bonner sticks, Shaun! I flew my Digimite for years! Even flew a couple of helis with it!
--
Pete
Re: When is a GEM not a GEM?
Posted: 26 Apr 2024, 17:37
by Tobe
Second Pete!
Re: When is a GEM not a GEM?
Posted: 26 Apr 2024, 21:26
by Shaun
You lads were real men with muscles on your fingers.
I've got delicate musicians fingers used to Sanwa, Multiplex and ball-raced sticks.

Re: When is a GEM not a GEM?
Posted: 26 Apr 2024, 21:28
by Shaun
Pchristy wrote: 26 Apr 2024, 17:29
Nothing wrong with Bonner sticks, Shaun! I flew my Digimite for years! Even flew a couple of helis with it!
Was that "flew" or crash avoidance on the heli's Pete.
