Just go to http://soldersmoke.com. On that archive page, just click on the blue hyperlinks and your audio player should play that episode.
http://soldersmoke.com
SolderSmoke Podcast #190 is available: http://soldersmoke.com/soldersmoke190.mp3 Pilgrims' Progress: Inspiring words from G3RJV BENCH REPORTS on JUNKBOX RIGS: Pete describes his beautiful 40 meter blue transceiver (video above) Bill describes his "Armand HROish" receiver BANDSWEEP! Bill needs small (yellow slug) 455 kc transformers. We need a good user-friendly 40673 SPICE model. SEND US YOUR BENCH REPORTS! The BD139 transistor Ferrite Core Matching Transformers QSO Reports: Getting on the air with HB rigs Bill's new FeelTech Signal Generator
It's worth noting that Mouser (still!) sells the "Yellow" 455 kHz IFTs (42IF101) along with four other models (search for "42IF"). Alas, they dropped the 10.7 MHz versions (usable from at least 5 MHz to 15 MHz) some time ago.
The lowest impedance of the bunch is for the 42IF102 (White - 30k:500Ohms) with an 8.1:1 ratio between the centertap/end and secondary (66:1 impedance transformation). A series of these with the properly-selected coupling capacitors can be made to provide a custom bandpass response (e.g. a transformer in/out, 2-3 units in the middle using only the resonated winding.)
To be sure, they can be run at different-than-intended impedances, but expect things to happen like lowering of Q, increasing of loss, etc. - but it can still be useful - particularly at <$1 each if you buy 10...
BG Micro has a 3 set of coils similar to the old coil set from Radio Shack. $1.80 with data sheet - http://www.bgmicro.com/set-of-3-if-transformers-50a01-a02-a03.aspx
"SolderSmoke -- Global Adventures in Wireless Electronics" is now available as an e-book for Amazon's Kindle.
Here's the site:
http://www.amazon.com/dp/B004V9FIVW
April 25, 2024. Meter Magic
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At times we need to include some form of metering in our homebrew rigs. No,
we will not be installing a Nano VNA in a transmitter. But often a current
mete...
VK6VZ looking for AM contacts with North America
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G'day
I am looking for AM contacts most days on 29.010MHz from 2300Z until after
0000Z.
I've been making CW contacts as far east as CT at this time (as ...
Trying a $15 70cm transceiver HK-188
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Peter, VK3YE, recently posted a video of a pair of 433Mhz transceivers he
bought at Aldi for $20. They worked OK but had a number of obvious annoying
probl...
An Inline RF Step Attenuator for QRPp Work
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I don’t need to explain the attraction of low power operation; if you’re
reading this, the chances are that you are already a convert. I’ve been
operating ...
Using an external clock with the RX-888 (Mk2)
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*The RX-888 (Mk2) and external clocking*
*Figure 1:*
The RX-888 with external clock input *(right)*
The enable/disable switch is barely
visible behind the...
A 51S-1 Restoration Story
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I came across my Collins 51S-1 in a big junkyard in Ankara, Turkey around
2012. It was in a pile with a lot of other electronic scrap, probably from
one o...
New QRP Cluster Online From OM0ET and OM6APN
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By DX EXPLORER
DX EXPLORER
Paul OM0ET and Peter OM6APN recently launched a new cluster dedicated to
QRP operations. Have a look and I hope you will enjoy...
3D Printing The Hadley 114mm Newtonian Telescope
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Yes, we’re building a 3D Printed Newtonian Telescope called Hadley. It’s
being printed in PETG and in the video below, I give a quick tour. My build
isn’...
3D printed project boxes
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I have been busy with some other things that have kept me away from
electronics projects for quite a while. Now I can get back to them, but
realize I n...
Daylight Again – An all Analog Radio
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What’s all this? In 10 seconds, A high performance, 7MHz, 5 watt SSB rig
Draws just 24 mA of current 90 dB dynamic range, 80 dB close-in dynamic
range 3D ...
Adding Enclosure to your sBitx Boards Order
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The early buyers of the sBitx board set who bought it for $270 USD might
want to also add the enclosure (box) for in the kit. What you will now get
is a f...
Digi-chirp! Digital synthesis of ‘nostalgic’ CW
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The bottom ends of 80, 40 and 20m are not what they used to be. For
starters, the busiest part is the digital segment where computers talk to
computers – l...
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A Simple Speech Processor
(For QRP/SSB Homebrew Transceivers )
Over the last few weeks I had been thinking to build a small AF speech
processor to add to...
A New Look for your uBitx!
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Adding a "Cool Blue" Display to your uBitx!
The standard "green background" with black lettering frequently reminds me
that I suffer from Chronic seasickn...
It's worth noting that Mouser (still!) sells the "Yellow" 455 kHz IFTs (42IF101) along with four other models (search for "42IF"). Alas, they dropped the 10.7 MHz versions (usable from at least 5 MHz to 15 MHz) some time ago.
ReplyDeleteThe lowest impedance of the bunch is for the 42IF102 (White - 30k:500Ohms) with an 8.1:1 ratio between the centertap/end and secondary (66:1 impedance transformation). A series of these with the properly-selected coupling capacitors can be made to provide a custom bandpass response (e.g. a transformer in/out, 2-3 units in the middle using only the resonated winding.)
To be sure, they can be run at different-than-intended impedances, but expect things to happen like lowering of Q, increasing of loss, etc. - but it can still be useful - particularly at <$1 each if you buy 10...
73
Hi Bill,
ReplyDeleteI seen these 455khz IF transformers on EBAY. I doubt you need 20 of them.....
http://www.ebay.com/itm/COILS-MITSUMI-AM-455khz-FI-20-PCS-YELLOW-MADE-IN-JAPAN-/172351382030?hash=item2820f1620e:g:oXcAAOSwAuNW5fcV
I probably have a couple in junk box, but stuff is still in storage. :(
Great broadcast as always....
73's
Dean AC9JQ
While part for projects are important, the photo tells the most important story.
ReplyDeleteThis comment has been removed by the author.
ReplyDeleteBG Micro has a 3 set of coils similar to the old coil set from Radio Shack. $1.80 with data sheet - http://www.bgmicro.com/set-of-3-if-transformers-50a01-a02-a03.aspx
ReplyDeleteThanks
Michael N9XYP