Re: [Discuss-gnuradio] Microtune 4937 RF module discontinued ...

[Alan Gray]

At 08:27 AM 22/07/03 -0500, you wrote:



> At 5:28 PM +1000 7/22/03, Alan Gray wrote:
> > I've had the same problems finding the 4937 tuner, and am currently in 
> > the process of adapting the hardware design to use a 4702 tuner module 
> > with an IF output at 36MHz. When we contacted Microtune they suggested 
> > using a tuner such as the 4702 and an additional downconversion stage 
> > (they suggested the NEC Electronics UPC2798GR which is apparently what 
> > they use in the 4937 tuners anyway)
> >
> > I've ordered a few of the NEC IC's but they're taking a long time to 
> > arrive. In the mean time I'm going to attempt to put together some 
> > hardware to use a 4702 module as is. I'm hoping that I should be able to 
> > sample the bandlimited signal without any downconversion (it's 
> > theoretically possible) and thus avoid the need for any more components.
>
> I've been shying away from Microtune since they and their manufacturers 
> rep for my area have been so difficult to work with. They sent me a sample 
> of the 4937 and swore up and down they still had them in stock (in the 
> Philippines) but for the life of me I could not get them to send me an 
> official quote.  I was all set to buy $1000 of tuners (their minimum 
> order) and told them the PO would be cut as soon as I got a quote, but 
> they don't seem to be interested in my business. (I tried for weeks to get 
> a quote.)  Given this experience, I am reluctant to jump to another 
> Microtune product.  If you're willing to do an external downconversion 
> from 36-44 MHz, it seems to me that there are a lot of tuners available to 
> consider... I've been looking at the Zarlink chips... Anyone else have any 
> good candidates?

I'm looking at using the 4702 chips primarily because I have a contact 
within Panasonic in Australia who has access to around 500 of these modules 
(around $7000 worth, give or take) and is, in his own words, "Looking to 
off-load them to a good cause" because they have no further use for them.

At the moment I have a box of 144 of the things sitting in a corner of my 
office and it seemed to be a waste not to at least attempt to use them. 
Unfortunately, as I'm in Australia, it's not really feasible for me to act 
as a distributor for these modules in ones and twos, as the time taken to 
export them and the costs involved would be rather prohibitive.

I think I have discussed the possibility of sending a bulk load of these 
tuners to someone in the US to distribute, however there didn't seem to be 
much interest at the time.

Regardless, I believe I've finished the design work and have put in orders 
for some parts, hopefully they'll arrive soon, and I'll be able to verify 
that I have a useful design.

Alan