Thanks for all the information that's been posted in response to mine and others' questions on this subject. I've certainly learned a lot that I never knew before.
Even though soldering all those wires onto veroboard is so tedious, especially when trying to pick up where you left of if you can't complete the job in one session (I usually write a list of connections to tick off as I do them, but invariably get engrossed and do a whole bunch without ticking them off), it's probably the easiest way with just primitive gear - as long as they keep making ICs in DIL packages... I'm largely ignorant of the analogue side of circuit design - induction effects (which I hadn't even considered until I read it here), input & output capacitance (info you see in the DC Characteristics tables of the datasheets). I'm surprised my spaghetti-heaps of wires and ICs work at all as I just connect up the logic and leave the rest to luck (I do remember to use decoupling capacitors though). I like Peter's idea of a tutorial on building Q40 add-ons. I'd like it to be in QL Today though :o) Ian. P.S. I've been getting more and more disappointed with Maplin, who have been steadily discontinuing their lines of older ICs. They now only supply microcontrollers, a very limited range of SRAM up to 128k x 8 and the range of crystals and crystal oscillators is seriously depleted. RS Components (www.rswww.com) still carries a broad range including many of the old 8 bit MPUs and peripheral chips, sourced from OKI. > -----Original Message----- > From: tony > Sent: 11 January 2002 18:31 > To: ql-users > Cc: tony > Subject: Re: [ql-users] Making PCBs (was Q40/Q60/??? Ultra IO card) > > > On Fri, 11 Jan 2002 at 12:44:08, wrote: > (ref: <H0000b5f11cf080d.1010753047.ln4p1327.ldn.swissbank.com@MHS>) > > >What equipment do you use to apply the etch-resist pattern to the > >boards, etch them, and then bond them together? > > > >Is it all very expensive for a hobbyist to produce one-off boards for > >experiments & prototypes? (Probably nothing as complicated as a Q40 > >board.) In comparison to, say, the cost of digital photography with > >film scanner, A3 printer, software, consumables? > > > >(Probably another stupid question from an ignoramus) > I didn't - this was done outside. One simply sends them plotter files > etc and they do it all from that. > > My one offs are breadboards. The sH was a sight to behold, but worked > incredibly well. > > I know Stuart Honeyball produced some commercial boards but printing > direct onto special film. > > How? He didn't have a laser printer at the time and I did > them for him > (8-)# > > It apparently worked very well, but there is loss of quality. > No chance > of .5mm romdisq type pitches by this method. > > -- > QBBS (QL fido BBS 2:257/67) +44(0)1442-828255 > mailto:[EMAIL PROTECTED] http://www.firshman.demon.co.uk > Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 > TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG > Visit our website at http://www.ubswarburg.com This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message which arise as a result of e-mail transmission. If verification is required please request a hard-copy version. This message is provided for informational purposes and should not be construed as a solicitation or offer to buy or sell any securities or related financial instruments.
