40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Entry  Mon Mar 28 17:06:15 2011, kiwamu, Update, Green Locking, a mixer school mixers.png
    Reply  Mon Mar 28 18:13:32 2011, rana, Update, Green Locking, a mixer school 
       Reply  Mon Mar 28 18:22:43 2011, kiwamu, Update, Green Locking, a mixer school 
Message ID: 4449     Entry time: Mon Mar 28 17:06:15 2011     Reply to this: 4450
Author: kiwamu 
Type: Update 
Category: Green Locking 
Subject: a mixer school 

In the last week Matt and I modified the MFD configuration because the mixer had been illegally used.

 

mixers.png

Since the output from the comparator is normally about 10 dBm, a 4-way power splitter reduced the power down to 4 dBm in each output port.

In order to reserve a 7 dBm signal to a level-7 mixer, we decided to use an asymmetric power splitter, which is just a combination of 2-way and 3-way splitter shown in the diagram above.

With this configuration we can reserve a 7 dBm signal for a mixer in the fine path.

However on the other hand we sacrificed the coarse path because the power going to the mixer is now 2.2 dBm in each port.

According to the data sheet for the mixer, 1 dB compression point for the RF input is 1dBm. Therefore we put a 1 dB attenuator for the RF port in the coarse system.

In the delay line of the fine path we found that the delay cable was quite lossy and it reduced the power from 2.2 dBm to about 0 dBm.

 

 

ELOG V3.1.3-