RE: RX2500, Homebrew or??

["Leif Åsbrink" <SMTP:LEIF.ASBRINK@xxxxxxxxxxxxxxxxxx>]

Hi All,

> After checking the price of getting an RX2500 over here in the 
> US, I started to look at the
> prices of a few parts to build one. It seems that currently the 
> RX2500 is about $455 USD
> with about $112 USD shipping (UPS, Problem is that the brown 
> trucks do not float).
Transportation is expensive but can be reduced if you have a friend
who also wants a unit...

> I wonder if there are import duties to be paid?
As far as I know there is no duty for import to the US.

> Thats nearly $600 and starts making 2 Time machines a bit more attractive
> $260 kit + shipping inside US.   Currently 1 Sek = $.115354 USD.
> The mixer IC's (74HC4052) are no problem at all at 23 cents each.
> I could not find the BUK 75150-55A on the internet for sale.
For the RX2500 you may use IRL510. At higher frequencies, 10.7MHz and
70MHz, I do not know any replacement but I am sure they exist. 

> I suspect it is not real expensive.
No. but it is hard to get.

> The  AD797 IC used for anti-aliasing was found 
> for  $8 each.
> Best I can determine, these are single
> section IC's , so 8 IC' are needed.
No. You did not count them all. There are 24 AD797 IC's in a
RX2500. Two channels, I and Q and some in the mixers.

> That's $64, making them the most expensive
> part of the project. 
So it is $192

> All the other parts look pretty ordinary
Yes.

> and low in cost.
Well, there are 22 rather expensive wound components also.

> Has anyone found a cost effective way to homebrew the RX2500 in 
> the US with
> US supplied parts? It seems oversees shipping is not too 
> practical. I wonder
> if the part supply problem can be solved, if a PCB is available somewhere?
You can download the CAD file and send it to any PCB manufacturer.

> Although the quality of the RX2500 is certainly high, I find it 
> expensive for its
> function. It would probably be more efficient if more circuits 
> were in the box, for the price. After all, it is basically just 
> a receiver converter.
The RX2500 is a cost effective solution if you need the performance
it offers. In case you do not need the dynamic range you have
many alternatives. You may use Tayloe mixers for example to
get a really low cost and probably better performance than 
available with the Time Machine. 

73

Leif / SM5BSZ

LINRADDARNIL