Analysis of cost to produce random serail generator.
At Hackers 8.0, we had a discussion about the feasability of someone building a random data generator. I volunteered to look into this with the hopes of making a cheap and inexpensive device that has 2 DB-9 connectors (Serial through box) to be used to generate random serial data at a particular baud rate. Today, I called Newbridge Micro, they faxed me the data sheets, and gave me the number for a local rep in San Jose. (408) 258-3600, but I was appalled at the price. They wanted $52.50 each in 100 quantity. So it is clear that if I use this chip, which really is a hybred, I cannot charge $50 each. So we have to decide what to do, or how much more it will cost. After examining the data sheet, the chip is probed by a pulse, and a bit comes out with an equal probability of a "1" or a "0". Sorta like a coin toss. I think that the perifery cost of the other electronics, such as shift registers, or UART which would be necessary to clock the bits into an 8 bit register, etc, would cost about $6 - $8 in cost, then I will have to fab the boards. I have friend at Douglas Electronics who can give me a good price. It would cost $150 setup charge for the PC boards and $2 per board. 1 ea RBG1210 $52.50 1 ea PC board $2.00 various chips $8.00 Setup $1.50 (1/100th setup charge) Total parts $63.50 (100 quantity) Cost (4 X parts) $254.00 So, it is clear that the cost is rather high, and not everyone can afford this. But if you think that people will want to buy it at that price, I can go ahead and do it, but the cost to me would be about $250 to build just one of them, and I have someone who can loan me the money to make a prototype. This also includes design time and use of an electronics lab to test and get it running. I wouldn't be able to borrow $6350 to build 100 of them, and I think I can talk the rep into letting me purchase them in smaller quantity, so I can build them on demand. I'm just not so sure that people will want to pay $254 for one of these. So please lets discuss this, among our group to determine if this price is reasonable. Although, it IS possible to use a cesium noise source (Don't know the cost of that) and perhaps I can cut that price down by about a half or a third, but the design time would be much increased, and perhaps there would be twice as much electronics, and perhaps the posibility that the randomness won't be as good. John D.
John Draper wrote:
[...] So, it is clear that the cost is rather high, [...] Although, it IS possible to use a cesium noise source [...] John D.
Geez... What happened to the idea of using a reversed-biased diode? That into a cheapy A/D and into a UART, should do the trick... Tim -- Internet: pozar@kumr.lns.com FidoNet: Tim Pozar @ 1:125/555 UUCP: ...!uunet!kumr.lns.com!pozar Snail: Tim Pozar / KKSF / 77 Maiden Lane / San Francisco CA 94108 / USA Voice: +1 415 788 2022
From: crunch@netcom.com (John Draper)
Although, it IS possible to use a cesium noise source (Don't know the cost of that) and perhaps I can cut that price down by about a half or a third, but the design time would be much increased, and perhaps there would be twice as much electronics, and perhaps the posibility that the randomness won't be as good.
Remember also that a radioactive source thats decaying fast enough to put out 20,000 bits a second the way the RBG1210 can isn't something you want to stand near.
Total parts $63.50 (100 quantity)
Cost (4 X parts) $254.00
I don't get this -- why is cost four times parts? Is that including profit? Also, shouldn't it just be possible to buy a couple of components and do as well as the Newbridge Micro unit? It would seem that we should be able to build something a lot cheaper than $52 if all we need is a noise source that will make a line go high or low on a clock input... Perry
participants (3)
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crunch@netcom.com
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pmetzger@shearson.com
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pozar@kumr.lns.com