24 July 2012

Raspberry PI from Farnell

Yesterday I received an email from Farnell stating that my RPi had been shipped (order #ORP051xxx). Since I ordered it the same day I submitted my order to RS, I was expecting a similar 11 weeks delivery time. But it got on my way about 50 days early. Could the recent increase in production capacity have something to do with it? Or most people ordered their copy from RS, since the communication was a tad better?

There is apparently no way to know which express courier Farnell used, nor to get a tracking number. On the other hand, RPi @ RS was paid right away, while Farnell charged my card on the shipping day.

Still no shipping news from RS, though.

21 July 2012

DX's EzTV668 lacks ESD protection diode too

It is amazingly easy to open the EzTV668 RTLSDR USB dongle bought at DealExtreme: make a little pressure with a small flat screwdriver on both sides of the USB connector and the cover will pop up.

I wanted to check whether my dongle has the ESD protection diodes installed...

I was not surprised to find an empty U7 location next to the antenna connector. BAV99 should be the part missing, which costs next to nothing. Plus shipping, of course.

19 July 2012

I.F.R. current

After adding the tuning knob and on request of a fellow builder, I checked the IFR current. The DVM read 16mA with a LCD without backlight. If you need a backlight then add the LED current, 10 to 20mA.

In cases where the power budget is strict, select an LCD that can be used in both cases (like the classic black/green) and add a switch for controlling backlight (or a trimpot).