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.

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.

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).

Raspberry PI: ordered

The "invitation to order" email came one day late and I have just paid for my RasPI. Order #127xxx, despatch expected within 11 weeks (or 77 days, or mid September).

COUNTDOWN TIMER WIDGET

(up here is a countdown widget in Flash, in case you don't see it)

avreal32 and lock bits

I feel dumb. I was expecting to see AVR's lock bits LB1 and LB2 amongst FUSES in avreal32 programmer, so I never saw that there is a dedicated option for preventing the readback of the chip content.

The command for locking an ATmega168 is (add your usual programmer definition and options):

avreal32 +mega168 -l2 (programmer parameters)

Neat.

SDR# on a Centrino CPU

Not a big achievement, but I want to report that I could use the RTLSDR dongle with SDR# on a laptop running WinXP with an Intel Centrino 1.6 GHz CPU. I have reduced the sampling to 1 Msps and the machine was running at 50% CPU: not bad for a 2004 computer! I listened to both WFM and SSB signals. There is probably room for a higher sampling rate, but keep in mind I have been listening to decoded output and not fed it over to another software (which in turn uses its share of CPU cycles).

23cm activity

These heard stations on 23cm SSB are some of the local big guns. Well, not so local given the DX distance of 136 km and my antenna consisting of an indoor dipole! But the HB9's were using 200W or more...

HB9BCD at 136 km

I1NDP and another QSO at 1'296'250 kHz

HB9SV at 136 km.

I do not like those aliasing products (or intermod?! or receiver overload?!), which then disappeared when I fiddled with SDR# settings. That effect requires further investigation.

My RX setup was not QRP either, since the i5 core laptop eats up a good deal of energy too (50W or so). I have already shaped up a biquad antenna. Now it needs a reflector and a support, then I am ready for the next 23cm event. Unless I manage to get a signal out of that SAT-TV PLL...