Low Value Precision Resistors / Quality 7805

[jonclancy]

Hi All,

I am gathering the parts for my DacKit and would like to use RC55Y 0.1% resistors from Welwyn. They have nearly all the values I need, but I am short of the 75 Ohm and 22.1 Ohm parts. Anyone know where I can source these low-value precision parts??

Also, can anyone recommend a make of 7805/7808 voltage regulators that are quality (and available to the UK)?

Finally, I'm seeking a quality 0.047uF PLL.

Everything else I have nailed - apart from a reasonable price for the TDA 1543. Reichelt have them for about 0.50UKP each, everywhere else is about 7UKP. My German is rubbish, so I get lost when ordering. Any suggestions, please??

Thanks very much in advance for the info. When I get the parts list sorted, I'll post the info here for others.

Cheers

Jon

 

[mozikluv]

7805/08 regulators

hi,

is LM7805/7808 made by National available in your place? have been using them and so far have not encountered problems.

 

[jonclancy]

Thanks......

Hi Mozikluv,

I have found that Farnell do the low-ish value 0.1 resistors. I have seen the 7805/8 regulators and have looked at the 2% tolerance MC7805ABT. We can get National products here, so I'll look again.

THANKS!



Jon

 

[fmak]

I am gathering the parts for my DacKit and would like to use RC55Y 0.1% resistors from Welwyn. They have nearly all the values I need, but I am short of the 75 Ohm and 22.1 Ohm parts. Anyone know where I can source these low-value precision parts??

Also, can anyone recommend a make of 7805/7808 voltage regulators that are quality (and available to the UK)?

Finally, I'm seeking a quality 0.047uF PLL.
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The RC55Ys are magnetic and I personally would use Dale RN55Cs but they are harder to get here. Easy from the States from Newark and cheaper than the RC55Ys. Otherwise Vishay VSRJs.

If you need one or two 75R Holcos or RN55cs; I can let you have them.

The best 780x I have come across are NJMs but you do need to measure the noise levels before installation These can be half as noisy as spec. Otherwise the best way is not to use them but to order LT low noise regulators (expensive becasues of carriage) with 20 to 40 uV specs. Don't be fooled by expensive looking LT 1085s or 1086; they are very noisy. Or splash out on two Audiocom Superregulators which have about 12 uV broadband noise.

You can get a NOT CHEAP NPO moulded ceramic from Farnell.

 

[jonclancy]

It's 1/2 term!!!

Thanks fmak,

lots of good guidance there. Lucky for me I've a week off work doing the 1/2 term duties - more time to make sure I get quality parts for my project!!

I am looking at using a 12vdc battery for powering my DAC, if that makes any difference to the choice of regulator.....

Cheers

Jon

 

[Zodiac]

For TDA1543 use a company called Grandata - www.grandata.co.uk I have ordered from them twice now, and their stuff is cheap and arrives quickly. They also have good stocks of hard to find japanese transistors like 2sk170 and the like.

I just checked their catalogue. TDA1543 are £1 each, plus you will have to pay £1 for postage.

 

[jonclancy]

Thanks.........

Thanks Zodiac - they do good deals on Sky sattelite accessoroes as well (just been looking).

Anyone else know of any other top suppliers (ie cheap, and holding the sort of stock we like!!!)?

I have got catalogues from Rapid, Maplin and Arrow, use RS and Farnell online and still find the component selection process a complete minefield!!

Catch you later!

Jon

 

[Zodiac]

For power supply caps have a look at www.greenweld.co.uk

They are a surplus supplier but have good range of BHC computer grade caps at v cheap prices

Z

 

[jonclancy]

Order is in...

..with Farnell. Just about to do Rapid. I had a look at Greenweld - their prices do seem to be very, very low (for instance the enclosures etc).

Thanks for the tip!!



Jon