The thing I find with Android phones is that each phone is treated differently, the makers support it for say 2 years with any updates, this is then passed onto the service providers, the carriers to implement as they see fit once they have customised it to suit their requirements, i.e. logo branding etc, sometimes the phones do not get upgraded at all because the providers don't think its worth while or because it costs them money. After the manufacturers of a particular model cease software support, that is the end of it, the providers are not expert enough to work with the phones feature set. We all know that Android is effectively freeware and each manufacturer is free to put their own twist on it to support features that they have built into their devices.
I have working Android phones here that are several years old HTC Desire, HTC One, Samsung Galaxy S3 and my latest one is Samsung J5(2016). All of them work perfectly OK and if I connect them to the network here and go to software update, there is no update for them. The last one was my J5(2016) which was a couple of months ago.
Why did I replace them, well the first one had a slide out keyboard which I found that I could not get on with as the keyboard would partial open up in my pocket and the phone switched on and drained the battery because the screen was on. The second one was working fine as a phone but many of the apps would not work anymore as they needed the latest version of Android which was not available to the phone because it was considered old. The Galaxy S3 was replaced because of water damage by dropping it in the bath so I purchased the J5 and subsequently I repaired the S3 and that one is now my back up phone and is also used as a mini tablet for games.
So my experience of Android seems to be vastly different from yours, I have never had any of my phones slow down apart from when the memory was full up or the battery was failing, both of which are easy to fix and the phones were made with easy to remove batteries without any need for tools and batteries are still freely available for all of them.
Added to that there is a thriving community of custom ROMS available that will allow the very latest versions of Android to run on them OK without problems and still work as SIM free phones on any network I chose.
Moving on because this is rapidly sliding into an Apple v Android debate and this not what I intended at all so back to the lovely T12 system.
I have modified my 9501 handle to accept the 4 core cable, removed the thermistor altogether and fitted the 4 pin plug from the handle that came with the Quicko and fitted that to the 9501 5 core lead with the white core chopped back and using the blue as the new white core as this core was already connected to the mercury / ball switch in the handle. The other end of this switch was disconnected from the earth tag and reconnected to the -ve tag as per Quicko handle and it works perfectly.
I agree the 9501 handle is better balanced in the hand and does give greater control over the tip in use.
When my ordered 4 pin plug is delivered I will fit this onto the Quicko handle so I'll have a spare handle available incase I need it. I have ordered another iron rest / support and will be very shortly ordering another system, just debating which one I should go with. I want to retain the menus system that this one has but do I go with another Quicko or another make altogether that uses the standard 5 pin system as per your diagram. which would probably make more sense.
Watch this space....
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