Was kind of bored last Sunday so decided to build something just for fun and no particular use.
After soldering it worked first time:
...no, it's not the frequency counter, is the circuit behind it!
General view of the assembly:
Excluding the oscilloscope, the counter on the image is now my bench frequency counter!
Focus on the oscillating circuit part:
Basically it's a Bitx V3 VFO with an J310 instead of the 2N3819 and with a double varicap in anti-fase (I could had done another arrangement with just one). The serial cap for the varicap part is 100pF and not 120pF as on the original, instead of 4-40 for the trimmer I used 10-60, the coil is a red core with around 25 turns (give or take). I used a 10K multiturn pot (5K on the original) and placed in series one 1N4001 diode on the ground leg to create a small minimum voltage for not getting too close to the varicap minimal bias.
Schematic:
It has around 100Khz of span, removing the series diode, using other type of variacp's and also a higher value in the series capacitor will extend the range.
I might add a mixer for a direct conversion receiver if I get bored again.
original schematic: http://yo2bzv.files.wordpress.com/2011/11/bitx20-v3varicap-e-preampl-micro-modf-con-q1-2sc2570a.gif
Have a nice week!
Homebrew of radio equipment, antennas, tuner, etc.
Monday, January 05, 2015
Saturday, January 03, 2015
Wireless router fix from the blog drafts and a cap/memory problem.
Sometimes I hate electronic devices as much as I love them.... that is... when they stop working.
Anyhow one of the devices that recently stop functioning was my home wireless router. No problem I connected the computer temporarily to the cable modem.
After some inspection I found a defunct cap near the power supply.
Replaced and voila, fixed.
I wrote this post originally maybe 2 years ago, was in the blog drafts and never published, honestly I don't remember (as of now) to have done this repair...I need some memory pills...
Have a nice weekend!
Anyhow one of the devices that recently stop functioning was my home wireless router. No problem I connected the computer temporarily to the cable modem.
After some inspection I found a defunct cap near the power supply.
Replaced and voila, fixed.
I wrote this post originally maybe 2 years ago, was in the blog drafts and never published, honestly I don't remember (as of now) to have done this repair...I need some memory pills...
Have a nice weekend!
Thursday, January 01, 2015
2015
Happy new year! With lot's of radio related activities!
The FT-102 with the new "feet" (high version) replaced last month. I just need to get the transverter to complete the line...
The FT-102 with the new "feet" (high version) replaced last month. I just need to get the transverter to complete the line...
Subscribe to:
Posts (Atom)