UR5FFR

Радиолюбительские конструкции и программы
It is currently 07 Jul 2020, 05:59

All times are UTC + 2 hours




Post new topic Reply to topic  [ 11 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Pico SWR
PostPosted: 01 May 2020, 04:53 
Offline

Joined: 30 Apr 2020, 15:23
Posts: 7
Позывной: yd3xxx
How to calibrate Pico SWR?


Top
 Profile  
 
PostPosted: 01 May 2020, 10:09 
Offline
Site Admin

Joined: 21 Apr 2012, 21:00
Posts: 616
Location: Odessa
Позывной: UR5FFR
1. Connect Pico SWR to computer, run software, select com-port and press open
2. Press "Calibration" button
3. Select "XTal frequency" tab. If you have frequency meter - connect it to Pico SWR out and measure frequency. If you haven't it - use crystal frequency. Enter frequency value in Hz. Press "Ok"
4. Select "Detector slope" tab. Disconnect load and press "Run". After calibration done press "Save"


Top
 Profile  
 
PostPosted: 01 May 2020, 10:30 
Offline

Joined: 30 Apr 2020, 15:23
Posts: 7
Позывной: yd3xxx
that's very helpful. I will try to fix. thank you
I'm still confused with T1. how to make it ... is it enough with the toroid wrapped around the cable


Top
 Profile  
 
PostPosted: 01 May 2020, 11:11 
Offline
Site Admin

Joined: 21 Apr 2012, 21:00
Posts: 616
Location: Odessa
Позывной: UR5FFR
Use next construction

Attachment:
14061_1.gif
14061_1.gif [ 11.35 KiB | Viewed 2545 times ]


Up wires to bridge R1R8R9, bottom - to ground and C17


Top
 Profile  
 
PostPosted: 01 May 2020, 16:52 
Offline

Joined: 30 Apr 2020, 15:23
Posts: 7
Позывной: yd3xxx
This construction that I made


Attachments:
IMG_20200501_202336.jpg
IMG_20200501_202336.jpg [ 1.13 MiB | Viewed 2510 times ]
Top
 Profile  
 
PostPosted: 01 May 2020, 16:58 
Offline
Site Admin

Joined: 21 Apr 2012, 21:00
Posts: 616
Location: Odessa
Позывной: UR5FFR
Yes, it's ok. Don't mismatch wire connection and all working as expected


Top
 Profile  
 
PostPosted: 01 May 2020, 17:05 
Offline

Joined: 30 Apr 2020, 15:23
Posts: 7
Позывной: yd3xxx
Results from circuit measurements. Not flat SWR 1: 1. whereas at the output output of 50 ohms. Statistik freq1,000,000-end 200,000,000, does this work well ...?


Attachments:
IMG_20200501_153717.jpg
IMG_20200501_153717.jpg [ 1.58 MiB | Viewed 2507 times ]
Top
 Profile  
 
PostPosted: 01 May 2020, 18:07 
Offline
Site Admin

Joined: 21 Apr 2012, 21:00
Posts: 616
Location: Odessa
Позывной: UR5FFR
Are your sure about 50R load? My 50R load - two smd 100R in parellel in SMA socket

Attachment:
swr50test.jpg
swr50test.jpg [ 177.34 KiB | Viewed 2497 times ]


Attachment:
rl50test.jpg
rl50test.jpg [ 127.46 KiB | Viewed 2497 times ]


Can you check voltage at BF998 drain? It must be in range 2.2v..2.8v
If you have thin 50R coaxial cable 2mm diameter try to make T1 from it.


Top
 Profile  
 
PostPosted: 02 May 2020, 15:49 
Offline

Joined: 30 Apr 2020, 15:23
Posts: 7
Позывной: yd3xxx
load 50R. but my TR 1 uses bf980 ... does this cause different results. because TR 1 is rare


Top
 Profile  
 
PostPosted: 02 May 2020, 21:28 
Offline
Site Admin

Joined: 21 Apr 2012, 21:00
Posts: 616
Location: Odessa
Позывной: UR5FFR
BF998 is very cheap transistor widely available. I haven't experience with BF980, but I think that all must be working same as with BF998. Anyway you need check voltage at drain - it must be in range 2.2v..2.8v.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 11 posts ]  Go to page 1, 2  Next

All times are UTC + 2 hours


Who is online

Users browsing this forum: No registered users and 0 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group