NBTV Newsletter.

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Postby Viewmaster » Sat Mar 23, 2013 8:05 pm

Steve Anderson wrote:
gary wrote:Does anyone know what the main objections actually are?

This may sound like whinging but IMHO it does put OS members at a significant disadvantage.

Agreed, and not whinging at all. But for me the printed version is a pain. Where did I put it? Heck, the dog's eaten it. I spilled coffee on it.


Get rid of the dog and use a straw. :) .....
..........or get a cat and drink tea. :lol:

I prefer the printed version, and have voted accordingly.
But then, no problem in postage delay being in the UK as we get it first
hot off the press.
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Postby Klaas Robers » Mon Mar 25, 2013 7:42 am

My Newsletter came the 22th of March. But I observed that the previous issue was in September. Did we go to a Newsletter of twice a year?

About the tolerances of the resistors in a 1-2-4-8 DAC:

The tolerance should be that close that the step size for all bits should have a precision of + or - a half step size of the least significant bit.

So:
- the highest resistor (12k) should be + 50% and - 25%, so + / - 37%
- The next resistor (6k8) should be 18%
- The next resistor (3k3) should be 9%
- The next resistor (1k6) should be 4.5%
- The next resistor (778) should be 2%

The internal resistance of the PIC ports is about 50 ohm.

So a 5 bits DAC needs only one resistor with a precision of 2%,
for the remaining 5% is good enough.

The 910 ohm is generating the sync pulse, who cares for a very precise sync pulse? So all resistors 5%, exept the 820, which is tuned to the optimal value by the 15k in parallel. For this 15k a tolerance of 5% is again good enough.
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Postby gary » Mon Mar 25, 2013 10:53 am

Steve Anderson wrote:Those that do not receive their copy by Monday the 25th, a quick post here saying so and I'll compile a list to Jeremy rather than him receiving multiple e-mails on the same subject.


I can confirm that mine has NOT arrived (Monday 25th).
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Postby Steve Anderson » Mon Mar 25, 2013 2:11 pm

gary wrote:I can confirm that mine has NOT arrived (Monday 25th).

I'll wait until Europe and the UK wake up, give them a few hours to report any non-deliveries, then zap an e-mail off to Jeremy. Not that there's anything he can do about it!

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Postby gary » Mon Mar 25, 2013 2:15 pm

Steve Anderson wrote:[ Not that there's anything he can do about it!

Steve A.


Well he can verify that they have been sent off and sent to the correct address (my last wasn't). If that checks out then I suppose we will have to wait another couple of weeks and then have them re-sent.
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Postby gary » Mon Mar 25, 2013 2:21 pm

DrZarkov wrote:Mine arrived today. Maybe the postman had to read it first. :lol:


Just for interests sake, Dr, is there a post date on the envelope? (assuming you have kept it).
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Postby Steve Anderson » Mon Mar 25, 2013 2:43 pm

Mine was dated the 7th March 2013.

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Postby gary » Mon Mar 25, 2013 3:04 pm

Steve Anderson wrote:Mine was dated the 7th March 2013.

Steve A.


In that case then it is not as late as I had thought - I always allow for 2-3 weeks. I don't think I have EVER received it in less than 2 weeks.

The strange thing then is how you and Andrew received it so quickly - most strange.

I would therefore be inclined to wait until the end of the week before hitting the panic button.


PS: It would be interesting to see what other post marks there are from various recipients - theoretically they should be the same or at worst the next business day I would have thought.
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Postby Dave Moll » Mon Mar 25, 2013 8:41 pm

Klaas Robers wrote:My Newsletter came the 22th of March. But I observed that the previous issue was in September. Did we go to a Newsletter of twice a year?

The latest issue was volume 38 no. 1. Volume 37 (2012) consisted of four issues, so it would appear that you have missed some. I would suggest checking what numbers appear on the issues that you have.
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Postby Steve Anderson » Mon Mar 25, 2013 8:51 pm

For the record,...

Vol. 37. No. 1 arrived here October 2011.

Vol. 37. No. 2. February 2012.

Vol. 37. No. 3. April 2012.

Vol. 37. No. 4. September 2012.

Vol. 38. No. 1. March 2013.

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Postby Ralph » Tue Mar 26, 2013 12:36 pm

Mine finally arrived in the post this morning (25 March). It if a good issue....

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Postby gary » Tue Mar 26, 2013 12:48 pm

Not here yet (March 26th)
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Postby Harry Dalek » Tue Mar 26, 2013 3:30 pm

gary wrote:Not here yet (March 26th)


I think coming by ship this time Gary :roll:

How many issues are there a year ? and if they have knocked it back is your member ship still one year or to number of newsletter issues ?.

I wish they could tell you via a forum PM to let you know if its running out i have no idea ,i think i have always kept it ahead just wondering if they let you know at all ?
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Postby gary » Tue Mar 26, 2013 3:46 pm

Harry, have a look inside the cover of a newsletter it is "published 4 times a year". Presumably if we have a situation where only 3 are published in a year then 5 will be published the next year and so on.

Keep in mind that, to a substantial degree, newsletter publication dates will be affected by the amount of material members are submitting - so if there is not enough material the newsletter is likely to be delayed.

Your membership subscription entitles you to one years membership, annually renewable.

I have my subscription paid automatically via paypal and therefore I am always paid up - "technically".

There used to be a code mark placed on the envelope of the newsletter to inform people if their subscription is due/over due. That was quite handy but I am not sure if they still do it.
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Postby gary » Tue Mar 26, 2013 3:51 pm

harry dalek wrote:I think coming by ship this time Gary :roll:


I am not so worried as I was - I expect it to arrive sometime this week going by past experience.

I do have an additional worry in that the last issue was sent to my old address (somehow my address didn't get updated). This was corrected by sending me another copy which arrived (quite quickly in retrospect) but until this new newsletter arrives I can't be sure if my address was corrected or not. Fingers crossed.
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