MY QO100 SETUP

Hi, anyone try this 1W amplifier ?

Hi,

A green dual Octagon LNB was modified for 25 MHz external reference. A damage was occured while opening it , a 78L05 was broken and it was replaced adding also a jumper wire as the PCB was removed. The L was added near the F connector and the C at the removed Xtal 25 MHz. The connection is with a teflon wire wrap cable. I was lucky and it was a single crystal one. About 3 dB SNR improvement was noticed. Also noticed a IF level increment of about 5 dB. The second output is ready for WB usage...

Hi,

A WB LNB bias tee (18V) with 1 dB loss.

Quote from SV1BDS

Hi,

A green dual Octagon LNB was modified for 25 MHz external reference. A damage was occured while opening it , a 78L05 was broken and it was replaced adding also a jumper wire as the PCB was removed. The L was added near the F connector and the C at the removed Xtal 25 MHz. The connection is with a teflon wire wrap cable. I was lucky and it was a single crystal one. About 3 dB SNR improvement was noticed. Also noticed a IF level increment of about 5 dB. The second output is ready for WB usage...

Hi, maybe the 25 MHz must connected to the other xtal pin !!!

Hi i2NDT ,

It must be the Detector Out & Enable pins of chips. Links : datasheet , product summary.

Can you verify this ? My order has not arrived yet.

Hi i2NDT , does the amplifier amplify small signals without applying anything to EN input ? Normally without any input at EN must work and applying gnd or Hi is disabled. Can you ask also the supplier of the pcb for instructions regarding this pin?

UPD: next to the 5 pin chip is a LED. May be this is an enable LED. Is this lighting ? Is this connected to the EN SKY's ? What is the voltage of the EN SKY's ?

Hi i2NDT can you post the message here to reply to all?

„i2NDT“ sent you a message on AMSAT Deutschland e.V. Forum:

hi George,

I measured my amplifier and found out that its power output is only 25dBm for 0dBm input.

power supply was 5V and consumption 500mA.

I guess that the difference (they said 30dBm output) is due to the fact that the amplifier is powered with 3,3V (on board LDO regulator) instead of 5V as per the datasheet...

BTW there is no need for a big heatsink as the sky65135 doesn't heat!

best 73

de

i2NDT Claudio

Hi i2NDT can you tell me the voltage at pins 4,11?

Quote from i2NDT

SV1BDS

on pin 4 it's 5V

pin 11 is 5V.

pin 16 and 13 (VCC1 and VCC2) are both 3,3V.

Hi Claudio,

This mean that it takes 5V at the final stage and not 3.3V.

Quote from i2NDT

yes, but driver and pre-driver get 3,3V instead of 5V.

all measurements on the datasheet are taken with VCC1, 2 and 3 at 5V.