Noise and sensitivity, v1.21 board

[alle...@gmail.com]

I recently purchased an upconverter and while it does work, on a short wire antenna (15') indoors it won't pick up anything but the really strong shortwave broadcasters. Nothing on the Ham bands! I guess shielding it and using a real antenna will work better. Going to install the software on a different computer and stick it in the shack with the "real" outdoors antenna.

Thanks,
Bill

[opendous]

A quarter-wavelength of 15' is approximately 16MHz so you should be able to pick something up.
http://www.onlineconversion.com/frequency_wavelength.htm

Getting the antenna outdoors is your best bet at picking up weak signals.

Using a balun will also improve reception as it will help match the large single wire impedance to the 50ohm of the Upconverter.
http://www.digikey.com/product-detail/en/CX2074NL/553-1655-ND
http://us.mouser.com/Search/Refine.aspx?Keyword=MABA-010143-FLUX18

I use my Upconverter indoors with a 120' antenna and balun to pick up my local time station around 7MHz.
http://en.wikipedia.org/wiki/Radio_clock

Grab a spool of wire, string it up indoors and see what happens.
http://www.digikey.com/product-detail/en/C2004A.12.01/C2004B-100-ND

[alle...@gmail.com]

OK _ update. I carried it down to the shack and hooked it up to my longwire that I use as my main antenna. Picks up much better, of course. Connected an MFJ259 to 20M dipole as signal source and used it to sync the frequency between the upconverter and my FT-707, adjusting the "-125 Mhz" offset so that the signals match.  I am still getting a LOT of images or birdies on the Rx. Maybe shielding it? I will post some photos.

Thanks,
Bill
AJ4TX

[alle...@gmail.com]

I took it down to the shack and connected it to the longwire antenna. Works much better, but I have a lot of images all over the place. I will post some photos, but I'm thinking I need to shield it, and add a BC band filter.

Also - I tried running it from a separate 5V supply. No different. Would rather run it from a different supply than use another USB cable, anyway.

73,
Bill

On Thursday, October 24, 2013 1:16:23 AM UTC-4, alle...@gmail.com wrote:

[opendous]

> Maybe shielding it?

  That will help.  Place some ESD static insulation foam on the top of the Upconverter, place the whole thing in a ziploc bag with holes cut out for the connectors, then wrap the whole thing in metal foil (preferably copper but aluminum will work) and connect the metal to the connector bulk.
http://media.digikey.com/Photos/3M%20Photos/8521.jpg

  NooElec is working on producing and selling custom-made enclosures for the Upconverter.

> tried running it from a separate 5V supply. No different

  Running the Upconverter off battery power is the best way to reduce noise (but not very convenient).

http://www.digikey.com/product-detail/en/BC3AAW/BC3AAW-ND
http://www.digikey.com/product-detail/en/LR6XWA%2FB/P646-ND/

[Joel Destrade]

Hello every body.
I'm new in this group and my English is not the best you have read...
I have an upconverte with a TERRATEC  dongle. My upconverter convert HF frequencies up to 125MHz. I have connected this installation to a long wire in the garden without balun or unun to reduce the noise. I think the noise is not more bad with my transceiver (A HB1B) and my end fed antenna on 40Meters band.
Perhaps changing the alimentation for a battery will be a good compromise. for information i have found very interesting batteries on aliexpress.com. They come from china and you musn't be in a hurry to have it but it has a very good capacity (9 Amperes per hour) on 12V. And it cost only 27.81$

(http://www.aliexpress.com/item/New-DC12V-Portable-9800mAhLi-ion-Super-Rechargeable-Battery-Pack-high-quality-for-wireless-transmitter-CCTV-camera/565999735.html).

It could be a good compromise for using on the upconverter.

I'll test so the antenna with my antenna tuner (MFJ 9201) who works very well with my transceiver.