FS: XA/XM/XE1541 adapters
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From: Mika Leinonen on 25 Jul 2007 02:01 I have some adapters built on factory made PCB:s, and will sell them for 15 euros + shipping cost. Price includes one DIN-6 connector on PCB and parallel connection header. Adapter is built to XA, XM, or XE by buyers choice. About 5 feet/1.8 m DIN-6 cable for +1 euro + shipping. I'll put pictures here: http://www.iki.fi/mkl/x/ (version 1.1 on the page) Shipping from Finland. Shipping costs begin from 1 euro in Europe. Reply to the Reply-To e-mail address.
From: Mika Leinonen on 3 Aug 2007 14:40 I put some XA1541 adapters to eBay.de, starting from 9.99 euros. I made the listings in hurry, so they tell that I'll ship to Germany, but I will send worldwide. On 2007-07-25, Mika Leinonen <mika.leinonen(a)tut.fi> wrote: > I have some adapters built on factory made PCB:s, and will sell > them for 15 euros + shipping cost. Price includes one DIN-6 connector > on PCB and parallel connection header. Adapter is built to XA, XM, or XE > by buyers choice. About 5 feet/1.8 m DIN-6 cable for +1 euro + shipping. > I'll put pictures here: http://www.iki.fi/mkl/x/ (version 1.1 on the page) > Shipping from Finland. Shipping costs begin from 1 euro in Europe. > Reply to the Reply-To e-mail address.
From: Wolfgang Moser on 4 Aug 2007 04:48 Hello Mika, Mika Leinonen schrieb: > I put some XA1541 adapters to eBay.de, starting from 9.99 euros. > I made the listings in hurry, so they tell that I'll ship to Germany, > but I will send worldwide. this is interesting. I'm not going to buy one since I made my own PCB based mini-series of 20 super small XAP adaptors (no XM or XE options) early this year. Your auctions will tell me, if there is a market for premium made adaptors like yours (with PCB, parallel cable connector, configuration options). Oh, btw., how are your experiences with the 2N7002 vertical D-MOS transistors or how are the experiences of your recent customers with that transistor type? Did you get some reports on which mainboard types your adaptor (XA configuration, 2N7002 transistor) was used? From my own experiences and measurements I expect the 2N7002 (as well as BS170 and 2N7000) as a fully compatible replacement for the BSV52, but Joe Forster (The Star Commander) and I never got much report from "in-the-field" users. Womo > On 2007-07-25, Mika Leinonen <mika.leinonen(a)tut.fi> wrote: >> I have some adapters built on factory made PCB:s, and will sell >> them for 15 euros + shipping cost. Price includes one DIN-6 connector >> on PCB and parallel connection header. Adapter is built to XA, XM, or XE >> by buyers choice. About 5 feet/1.8 m DIN-6 cable for +1 euro + shipping. >> I'll put pictures here: http://www.iki.fi/mkl/x/ (version 1.1 on the page) >> Shipping from Finland. Shipping costs begin from 1 euro in Europe. >> Reply to the Reply-To e-mail address.
From: Mika Leinonen on 4 Aug 2007 11:03 On 2007-08-04, Wolfgang Moser <wn0612(a)d81.de.invalid> wrote: > Oh, btw., how are your experiences with the 2N7002 > vertical D-MOS transistors or how are the experiences I have sold one of these adapters with 2N7002, and it worked. I sold it as an replacement for an adapter with BAT54 diodes, because the latter didn't work in his PC. Could it be that BAT54 is not a compatible SMD equivalent with BAT85? (Must check the datasheets again.)
From: Wolfgang Moser on 4 Aug 2007 17:29
Hi Mika, Mika Leinonen schrieb: > On 2007-08-04, Wolfgang Moser <wn0612(a)d81.de.invalid> wrote: >> Oh, btw., how are your experiences with the 2N7002 >> vertical D-MOS transistors or how are the experiences > > I have sold one of these adapters with 2N7002, and it worked. > I sold it as an replacement for an adapter with BAT54 diodes, > because the latter didn't work in his PC. In 1999/2000 there was a similar situation with a very small number of The Star Commander beta testers and the XE1541 cable and ended up in the transistor design.. > Could it be that > BAT54 is not a compatible SMD equivalent with BAT85? > (Must check the datasheets again.) Hmmmmm, the Philips datasheet of that type mentions a forward voltage of 320mV, when there is a current of 1mA. At a current of 10mA the drop voltages goes up to 400mV. With one floppy disk drive, there's a pullup resistor of 1K Ohm per IEC bus line, at 5V this results in a current of 5mA for the driver that takes a line to low level. In this situation the drop voltage could be at 350mV. Now, much depends on the low level the LPT port driver does generate. If it is true TTL logic, it could be found at around 0.8V. From the Schottky diode 0.35V are added which results in 1.15V. This voltage must be "low enough" to successfully drive the 74LS14 Schmitt Trigger within the floppy to a low level. Now, I known of some 1541-Ii disk drives that do not contain a Schmitt Trigger, but a standard 74LS04 inverter. All I want to say is: It is very, very difficult to estimate compatibility and resulting software behavior from watching a single component only. For the Schottky diodes you should always look for types with the lowest possible drop voltage at higher currents. A drop voltage of only 0.2V at a current of maybe 30mA would be even better than the 1N5819 or BAT85 types. To give your a more concrete answer: From looking to the datasheets and without doing some measurements, I'm not able to tell you, "how much compatible" the BAT54 is in comparison to the BAT85. Womo |