Wave Bubble 2010 Moderators: adafruit_support_bill, adafruit

[Mictronics]

For the following two plots the VCOs were tuned to there minimum frequency.
The digital potentiometer were set to maximum sawtooth amplitude, with NE555 set to high freqeuncy sawtooth mode.

Low band VCO, minimum frequency tuned, maximum sawtooth sweep

ESPI-ESPI@2010-09-26_23-50-56.png (7.14 KiB) Viewed 3975 times

High band VCO, minimum frequency tuned, maximum sawtooth sweep

ESPI-ESPI@2010-09-26_23-35-01.png (6.46 KiB) Viewed 3975 times

You can see the generated bandwidth of the VCO signal covers a few 100MHz on full sawtooth amplitude.
In my opinion this should be changed to cover maybe just 100MHz bandwidth at full amplidute.
Cause otherwise the bandwidth resolution which could be set by the digital potentiometer is quite low. A few KHz bandwidth per digit would be fine.

[Mictronics]

Here are two plots of the output power over the full VCO frequency range.

Low band VCO, full span output power sweep

ESPI-ESPI@2010-09-27_01-03-04.png (6.33 KiB) Viewed 3974 times

High band VCO, full span output power sweep

ESPI-ESPI@2010-09-27_01-25-13.png (6.28 KiB) Viewed 3974 times

Input level to PLL (with T-Attenuator between VCO and PLL):
Low band: -7dBm to -12dBm
High band: -8dBm to -20dBm

Next step will be testing the gain stage.

[skygear]

i'm getting very excited looks promising so far...

aqisnotliquid --->the black pcbs are a go for me by the way< if everything works out lets get a thread together for a bulk order

[Mictronics]

So folks, here are the results from measurements with amplifier installed.

The amplifier is a GALI-84. Bias resistor is 1 Ohm and Vcc 5.8V. Both amplifier stages drawing a bit more than 100mA.

High Band, Max Power 1575MHz

ESPI-ESPI@2010-10-18_03-27-54.png (8.6 KiB) Viewed 3851 times

High Band , Average Power 2450MHz

ESPI-ESPI@2010-10-18_03-24-57.png (7.95 KiB) Viewed 3851 times

High Band, Max Power 2450MHz

ESPI-ESPI@2010-10-18_03-29-07.png (8.61 KiB) Viewed 3851 times

[Mictronics]

High Band, Average Power 1575MHz

ESPI-ESPI@2010-10-18_03-27-23.png (8.25 KiB) Viewed 3851 times

Low Band, Average 350MHz

ESPI-ESPI@2010-10-18_03-37-20.png (8.02 KiB) Viewed 3851 times

Low Band, Max Power 350MHz

ESPI-ESPI@2010-10-18_03-37-36.png (8.69 KiB) Viewed 3851 times

[Mictronics]

Low Band, Average Power 1280MHz

ESPI-ESPI@2010-10-18_03-40-28.png (8.52 KiB) Viewed 3851 times

Low Band, Average Power 1280MHz

ESPI-ESPI@2010-10-18_03-40-28.png (8.52 KiB) Viewed 3851 times

All in all the output power over the low band is around 10-14dBm average and 18-21dBm max power.
High band 7-14dBm averange and 14-20dBm max power.

[Mictronics]

Forgot one plot, 100MHz sweep from 2400-2500MHz, max power:

100MHz sweep, 2400-2500MHz, max power

ESPI-ESPI@2010-10-18_03-54-56.png (8.92 KiB) Viewed 3849 times

[aqisnotliquid]

The plots look great. I'm waiting for the final go ahead to put out a batch order.

[losthorizonmba]

Please count me in when you order batch of boards. Can make deposit

[javajax]

Let me know when you are doing the batch order I'll go in on it.

[akula169]

Add me to the list as well

[razorskiss1000]

I would be interested as well. So excited for this.

[jarsnah12]

I too would be interested. Let me know what the final cost would be to add me to the order.

[echomike]

also add me!

[TheFallen]

Just a thought an ATMega16u4 is a couple of quid cheaper than an FT232 and can do the sample function as a USB-serial converter, but then gives you a load of extra IO pins!!!!!!
See the Teensy for more inspiration.