25 boards arrived today :). I will post an update when they will be available for sale shortly…
The TDX card is designed to work with power speakers. Though you can use headphones you can’t obviously adjust the volume :). I was looking around on ebay and came across a smart little headphone amplifier by FiiO that works very well with the TDX card. It is the E5 model and has volume control, and bass switch as well as a re-chargable battery (via USB) that apparantly gives you about 20 hours of use. Quite handy if you want to use headphones when the misses doesn’t want to hear the tink tink of 80’s computer music ;). It was only about £9 here in the UK and looking at the USA Ebay site think you can get it cheaper.
The Drew ][ TDX version 1.1 board are now available to order 🙂
The version 1.1 boards have turned up. This is another 20 board run, and will post more details once I have confirmed costs and when I can get them ready. I am aiming for £26.99 (this is without back plate, but has an onboard 3.5mm jack and a connector for backplate from version 1.0 card). This card will just be stereo output only, and will include the better demux chip.
While I wait for the speakers to turn up for the laptop GS card, I have decided to look at the redesign of the TDX version 1.0 board. I am now looking at smaller board, with 2 layers (one for gound plane) and an onboard jack. I will also leave a connector on their so if anyone has a version 1.0 board they can use the existing connector (I will also be offering the connectors as well). This is an effort to get the boards cost down and offer them at a better price. Though the first board was offered for sale, this time round i would like to cover most of my costs ;-).
Currently looking something like this :-
Ever since I started this project I had noticed a small issue where occasionally you would hear sound/artifact on the wrong channel. I noticed this most notably in the game Silpheed on the intro music…(believe me I spent a lot of time just sitting there listening to it lol). I had chosen to ignore this as my Audio Animator also did this, so I chose to accept that either I was hearing things and being rather anally retentive or hardware does something a little differently to emulation (All I could compare too). With the Apple IIGS Hardware guide also suggesting to use the MC14052 Demux I concluded that its just the way it is…
Well it seems the I chose to ignore my advice and recently picked up some other newer demux chips by Philips (74HC4052N and/or 74HCT4052N). These have a quicker switch rate than the MC15042B and are pin compatible and I was pleased to hear that the issue went away 🙂
I will look at sending out replacement demux switches FOC to everyone that purchased a card over the next few months and once the laptop cards gets all completed. You will then be able to just remove the MC14052 and drop in the new one. You probably won’t even notice the issue on your card when you using speakers as I spent a lot of time with headphones, which makes it more noticeable, so don’t panic 😉