Re: "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B
Karl is right and it¡¯s almost embarrassingly simple compared to what folks had to go thru in the old days. ?
I built a Mini R2 a couple years ago using the phase shift feature in the QRP Labs VFO and a DPDT switch to flip the channels from usb to lsb, and I encourage anyone to try that as it really simplifies the I/Q projects.
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On Nov 26, 2019, at 12:33 PM, Karl Heinz Kremer - K5KHK < khk@...> wrote: With the?Si5351 you can actually create quadrature clock signals directly -?al least for frequencies starting in?the 80m band if I remember correctly.??See Hans'?writeup in a recent QRP Quarterly (again, if I remember correctly - I read too much stuff and sometimes it's hard to remember where I saw something :) )
Karl Heinz - K5KHK
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Re: Replacing SBL-1 with hand built mixer?
I tried homebrew mixers using BAT54S and BN43-2402 cores, they work just fine.
For use with Si5351A? I prefer KISS mixer built on FSA3157 or SN74LVC1G3157 parts. Look for Chris N7ZWY articles about it.
These parts can use 3.3V supply and in this case interface directly to the Si5351 output with perfect level matching.
This mixer also saves 1 transformer.
Another application I tried was RTL-SDR upconverter with 5V supply and 50MHz crystal oscillator LO, also with good results.
Look for bigger SOT-23-6 package. I bought some in smaller SC-70 package, these are more difficult to handle.
73, Mike AF7KR
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Re: Replacing SBL-1 with hand built mixer?
Cory and the group:
As mentioned, the NE602 (SA612, NE6xx, etc -- they're all the same chip) is a handy device indeed, but it's not a replacement for an SBL-1 diode-ring mixer.
The biggest factor in comparing the two is dynamic range and RF performance. The SBL-1 (any diode-ring mixer) offers significantly better RF performance, dynamic range, etc.
It requires more parts, more "VFO drive" and a post-mixer amplifier, but it's a sledge hammer compared to a tack hammer.
Each has its place, of course. :)
Regards,
--Kirk, NT0Z ? Rochester, MN
My book, "Stealth Amateur Radio," is now available from
www.stealthamateur.com and on the Amazon Kindle (soon)
On Tuesday, November 26, 2019, 10:00:14 AM CST, Cory KG7BBV <cory.goates@...> wrote:
From looking around online, couldn't you use an NE602 in place of an SBL-1? They're definitely cheaper.
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Re: "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B
With the?Si5351 you can actually create quadrature clock signals directly -?al least for frequencies starting in?the 80m band if I remember correctly.??See Hans'?writeup in a recent QRP Quarterly (again, if I remember correctly - I read too much stuff and sometimes it's hard to remember where I saw something :) )
Karl Heinz - K5KHK
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Re: Replacing SBL-1 with hand built mixer?
If you want cheap and homebrew, I'd duplicate the mixers on the uBitx from HFSignals.
Farhan gives his recipe for the transformers in the circuit description.
The Bat54s diodes on the uBitx are Schottky, so half the threshold of the 1n4148's on a Bitx40,
and thus only 7 dBm of power required from the VFO versus 14 dBm for the 1n4148's.
(I doubt the Bitx40's si5351 + 6db attenuator gives anything like 14 dBm, but it works well enough.)
The Bat54s package provides two matched diodes.? ?
There are 4 diodes in the complete mixer, but only two are conducting for each half of the clock cycle.
Each set of two diodes that are simultaneously conducting should be matched.
The SBL-1 and ADE-1 are level 7 mixers (7 dBm of VFO energy required for optimum performance).
The SBL-1 has been around for maybe 40 years, there are many (good?? bad?) clones on ebay.
Hams reading old QST articles tend to buy SBL-1's (and 40673's and 811 vacuum tubes).
The ADE-1 is roughly equivalent, but in a modern surface mount package.
Half the price of an SBL-1 when buying at quantity 20 or more from MicroCircuits.
If you want uniform performance across 1 to 500 mhz, you probably want to buy directly from MiniCircuits.
If all you want is something that works at 7mhz, go ahead and roll your own if so inclined.
The SA612 mixers are fine for many applications, but not a drop in replacement for a diode ring mixer.
The SA612 has about 14 dB of gain (vs about 6dB of loss through a diode ring), and requires far less?
energy from the oscillator.? You can use the oscillator provided on the same chip if you wish.
However, the SA612 does not have nearly as much dynamic range.
A good choice for battery powered equipment, often works well if there is plenty of selectivity
(perhaps a crystal filter) up front to knock out strong adjacent signals that might saturate it.
Jerry, KE7ER
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On Sat, Nov 23, 2019 at 03:38 PM, Ryan Flowers wrote:
Hi everyone,
I'm looking at many circuits and I see the ones that reference using the SBL-1 mixer. Is there any reason not to just build a double balanced diode ring mixer with discrete components instead? I'm referring to this mixer, which has a schematic that really seems to be the same as a double balanced diode ring mixer.?
Thanks for any pointers :)?
--
Ryan Flowers W7RLF
https://miscdotgeek.com
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Re: "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B
Building phase shift networks or fabbing a board for some DDS chips in TQFP packages?
strikes me as the hard way to create a quadrature clock.
Could use a 7474 dual D-FlipFlop as done on the $21 Softrock Lite II:??
Requires a VFO (such as the $1 Si5351 plus a $1 microcontroller) operating at 4x the operating frequency,?
Or buy the RX-Ensemble kit for $64, general coverage and includes an si570 clock source.
Either one is emitting quadrature baseband audio, you could hook it up to your stereo amp
for Binaural audio, instead of using a computer soundcard and decoding stuff digitally.
.
Jerry, KE7ER
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On Thu, Nov 21, 2019 at 04:50 PM, Bob Clarke wrote:
One alternative to phasing networks in quadrature downconverters is to use two sources with a common reference, on the same frequency but 90 degrees out of phase.
You can do this with a dual DDS IC or two DDS ICs (or two fractional-N PLL/VCOs with the phase programming feature) with a bit of calibration. You can then, as Rick Campbell KK7B?
does in his QST article, drive a pair of audio phase shift networks to complete the image-reject downconverter.
?
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Re: Replacing SBL-1 with hand built mixer?
From looking around online, couldn't you use an NE602 in place of an SBL-1? They're definitely cheaper.
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Re: Replacing SBL-1 with hand built mixer?
Diz used to sell a DBM kit:??
I used a couple in project and they worked well.
Although he no longer sells this kit, his design might provide some food for thought.
cheers, Graham ve3gtc
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Re: Replacing SBL-1 with hand built mixer?
Thank you, gents! I appreciate the assistance and understanding. Given the low-buck nature of anything I do, I'm quite alright with a hand built mixer vs a pre-made mixer, even if it is smaller and higher performing :)? 73! --
Ryan Flowers W7RLF
https://miscdotgeek.com
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Switch-mode, consumer grade power "cubes" (AKA: Wall Warts) are a menace and, to a lesser degree, any consumer grade device containing a microprocessor.??
Most Internet modems, routers and other network peripherals are powered from 12 Volts D.C..? Here, I power my cable modem, wifi router and VOIP ATA from a 12 Volt backup 'box' made by Belkin.? 86'd the three wall warts that formerly powered the three.? Those 3 boxes are about 4-5 feet from my operating position and about 6 feet from the floor (to get the wifi router antennas as high as practical). Now, things are considerably less noisy, in fact, I hardly hear them if at all.? My direct ethernet cable connection from the router to the shack PC is CAT-5E cable and it's quiet without additional ferrites, so far.?
There is something else that clobbers me at this location but it's coming in from the outside world on the A.C. power line drop; likely from a neighbor.? I chased one noise source for nearly a day and found a defective charger for one of my DMR handhelds to be the culprit.? Sounded like a sawmill at full song.? It got the hammer.
I concur with filters on the network (and wall wart) cables but I'd first try ruling out the warts by powering the network equipment on batteries as a test.? ?
Best of luck finding your interference and
73.......Steve Smith WB6TNL
? ? ? ? ? ? ? ? "Snort Rosin"
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My thoughts are with the switching power supply. Test it with a test load, anything really.?
Hi Curt,
A 3 pound sledge hammer comes quickly to mind. But then you will be
without your WIFI :(
Lucky me - I don't hear my WIFI in my radios. The router is halfway to
the other end of the house. My radios are at either end of the house
(two locations). Others have tamed the router rfi the same way I have
tamed noises from some of my other computer gear. Try some ferrite
chokes on external leads from the router - especially the power supply.
Sometimes the beast is the power supply itself. Most are 5 volt DC power
supplies and they are switchers. Hams have replaced the switchers with
good linear regulated supplied. Those are much more civilized.
So try filtering at or near the WIFI unit. Try relocating the router
farther from your radios. And use coax with your antennas to at least
get outside the house (farther away from the router). I use end fed
wires that come right into the shack sometimes and they are much more
sensitive to such RFI sources.
Good luck with your evil router. Go tame that beast!
73,
Bill? KU8H
On 11/24/19 6:56 AM, Curt via Groups.Io wrote:
> Since this is a "tech" group, want to know if others have experienced
> and solved WIFI RFI.
>
> I own a Netgear 6300 "Smart" WIFI router that is located inside the
> shack on desk near the operating position.? I experience "motorboat"
> interference on HF, all bands.? I originally thought it was a problem in
> one of my older transceivers ( Triton IV ) with the audio amplifier and
> nearly dismantled the radio until heard it in another radio and traced
> it to the router.
>
> Thoughts?
>
--
bark less - wag more
-- Ryan Flowers W7RLF
https://miscdotgeek.com
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Re: "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B
Thanks Nick.? That¡¯s quite an ambitious project. Mike K5ESS ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Nick Kennedy
Sent: Sunday, November 24, 2019 8:13 AM
To: [email protected]
Subject: Re: [qrptech] "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B ? See AA0ZZ's article on the IQ Pro with the AD9854 in the May/June 2006 QST.?? ? On Sat, Nov 23, 2019 at 10:21 PM K5ESS via Groups.Io <k5ess.nothdurft=[email protected]> wrote: Has anyone used an AD9854 DDS to provide a quadrature LO? Mike K5ESS ?
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Hi Curt,
A 3 pound sledge hammer comes quickly to mind. But then you will be without your WIFI :(
Lucky me - I don't hear my WIFI in my radios. The router is halfway to the other end of the house. My radios are at either end of the house (two locations). Others have tamed the router rfi the same way I have tamed noises from some of my other computer gear. Try some ferrite chokes on external leads from the router - especially the power supply. Sometimes the beast is the power supply itself. Most are 5 volt DC power supplies and they are switchers. Hams have replaced the switchers with good linear regulated supplied. Those are much more civilized.
So try filtering at or near the WIFI unit. Try relocating the router farther from your radios. And use coax with your antennas to at least get outside the house (farther away from the router). I use end fed wires that come right into the shack sometimes and they are much more sensitive to such RFI sources.
Good luck with your evil router. Go tame that beast!
73,
Bill KU8H
toggle quoted message
Show quoted text
On 11/24/19 6:56 AM, Curt via Groups.Io wrote: Since this is a "tech" group, want to know if others have experienced and solved WIFI RFI.
I own a Netgear 6300 "Smart" WIFI router that is located inside the shack on desk near the operating position.? I experience "motorboat" interference on HF, all bands.? I originally thought it was a problem in one of my older transceivers ( Triton IV ) with the audio amplifier and nearly dismantled the radio until heard it in another radio and traced it to the router.
Thoughts?
--
bark less - wag more
|
Re: "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B
See AA0ZZ's article on the IQ Pro with the AD9854 in the May/June 2006 QST.??
?
73-
Nick, WA5BDU ?
On Sat, Nov 23, 2019 at 10:21 PM K5ESS via Groups.Io <k5ess.nothdurft= [email protected]> wrote: Has anyone used an AD9854 DDS to provide a quadrature LO? Mike K5ESS ?
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Re: Replacing SBL-1 with hand built mixer?
Ryan,
What you suggest is just what Farhan has done with his BITX and uBITX radios.
Ben, K0IKR
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Since this is a "tech" group, want to know if others have experienced and solved WIFI RFI.
I own a Netgear 6300 "Smart" WIFI router that is located inside the shack on desk near the operating position.? I experience "motorboat" interference on HF, all bands.? I originally thought it was a problem in one of my older transceivers ( Triton IV ) with the audio amplifier and nearly dismantled the radio until heard it in another radio and traced it to the router.
Thoughts?
|
Re: "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B
Has anyone used an AD9854 DDS to provide a quadrature LO? Mike K5ESS ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Bob Clarke
Sent: Thursday, November 21, 2019 6:44 PM
To: [email protected]
Subject: Re: [qrptech] "A Binaural IQ Receiver" QST Mar 1999 Campbell KK7B ? One alternative to phasing networks in quadrature downconverters is to use two sources with a common reference, on the same frequency but 90 degrees out of phase. You can do this with a dual DDS IC or two DDS ICs (or two fractional-N PLL/VCOs with the phase programming feature) with a bit of calibration. You can then, as Rick Campbell KK7B? does in his QST article, drive a pair of audio phase shift networks to complete the image-reject downconverter. ? Bob, N1RC ? ? On Thu, Nov 14, 2019 at 11:30 PM Ted KX4OM via Groups.Io <wirehead73=[email protected]> wrote: Jeff Damm, WA7MLH has a couple of diode ring boards shared on Osh Park. The ones here use Bat54S dual diodes. When you order a shared project, you get 3 boards for the listed price. I have ordered from them. Many of you know Jeff as a collaborator/contributor of stuff in EMRFD. He also has a version of the Hybrid Cascode IF Amplifier that he created, along with a general purpose "bench" HyCas design.
The other board, modular for a project, is on page 1
Ted, KX4OM
--
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Re: Replacing SBL-1 with hand built mixer?
What Kirk said.
I will add: size.? Unless you have teeny-tiny fingers :-P you won't be able to duplicate an SBL-1, HA!
However, for ham HF use and if assembled properly, a HB DBM will function just fine.? Proof:? Jim Kortge's
2N2/40 and 40+: <?
73.......Steve Smith WB6TNL
? ? ? ? ? ? ? ? "Snort Rosin"
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Re: Replacing SBL-1 with hand built mixer?
Hey, Ryan,
The schematic looks exactly like a double-balanced mixer because it is! :)?? Exactly.
And yes, you can build your own, but you may not experience the same level of performance with your home-brew DBMs. It's difficult to achieve identical windings when making these by hand, and the diodes MC uses are optimized for the purpose (ours' almost certainly aren't). Then there's the SBL-1's shielding, which is probably different from home-brew DBMs (many of which are completely unshielded).
In short, you can roll your own. I have done it several times, but I almost always use SBL-1s now (big cache on hand) or ADE-1s (lesser cache). My home-brew radios need all of the mixer performance they can muster, which leave a bit of headroom for me to mess things up elsewhere (typically impedance matching?).
Regards,
--Kirk, NT0Z ? Rochester, MN
My book, "Stealth Amateur Radio," is now available from
www.stealthamateur.com and on the Amazon Kindle (soon)
On Saturday, November 23, 2019, 5:38:48 PM CST, Ryan Flowers <geocrasher@...> wrote:
Hi everyone, I'm looking at many circuits and I see the ones that reference using the SBL-1 mixer. Is there any reason not to just build a double balanced diode ring mixer with discrete components instead? I'm referring to this mixer, which has a schematic that really seems to be the same as a double balanced diode ring mixer.? Thanks for any pointers :)? --
Ryan Flowers W7RLF
https://miscdotgeek.com
|
Replacing SBL-1 with hand built mixer?
Hi everyone, I'm looking at many circuits and I see the ones that reference using the SBL-1 mixer. Is there any reason not to just build a double balanced diode ring mixer with discrete components instead? I'm referring to this mixer, which has a schematic that really seems to be the same as a double balanced diode ring mixer.? Thanks for any pointers :)? --
Ryan Flowers W7RLF
https://miscdotgeek.com
|
Kirk Kleinschmidt, NT0Z
Nick Kennedy