Re: Latest from MPJA ,... including Pack of 10- IRF510 N Channel FET Transistor 100V output transistors
I have no idea if you have bad URF520's.
What I know is that the only IRF510's that Mouser and Digikey
have carried over the last 10 years or so have been Vishay/Siliconix.
Jerry, KE7ER
toggle quoted message
Show quoted text
On Wed, Apr 14, 2021 at 04:42 PM, Bob Lunsford wrote:
I guess I have some LF power FETs, then.
|
Re: Linear Amplifier Build
Look on youtube for LDMOS. Build up to 11K by adding pills. On Sun, Apr 11, 2021 at 5:04 PM jerry@... <jerry@...> wrote:
On 2021-04-11 12:41, Rafael Diniz wrote:
Hi Jerry,
Which transistors are in the finals of this kit you bought? MRF300AN and MRF300BN. They are said to have an in-circuit gain of
20dB.
If that's true, then 6W in - gets you 600W out.
- Jerry KF6VB
I'm using a BLF9120 based kit I bought on aliexpress, it works pretty
well, but up to 100W at most.
Rafael
PU2UIT
On 4/11/21 12:59 PM, jerry@... wrote:
All,
I know this isn't the right forum for this - anybody know of
a forum for people building linear amps?
Last night, I had my first contact in some years. A pleasant
gentleman in Calgary. Unfortunately, he could not hear me as well as
I heard him, and we had to cut it short. So frustrating! I was
reminded of why we have linear amps. I was running barefoot, 100W.
So this morning, I hauled the 30L-1 out of the shed. Oh my aching
back! The 30L-1 is a 60's vintage Collins linear with 4 811-A tubes.
It's big. It's heavy. It does Not Belong in this bedroom.
I'm looking forward to building the LDMOS amp that I ordered on
Ebay.
Also looking forward to the uBITX transceiver.
For me, ham radio is about two things - building equipment, and
chatting about building equipment :).
- Jerry KF6VB
On 2021-04-11 07:50, Evan Hand wrote:
Jerry,
I did do the testing of my modified v4 against my unmodified v5. I
have posted the power levels of the v4 on this thread. The IMD
measurements that I got are as follows:
Modified v4:
80meters: -21db
40meters: -19db
20meters: -20db
Unmodified v5:
80meters: -22db
40meters: -21db
20meters: -19db
As far as I can tell there is not really much difference in the SSB
performance with the change of C81 to 2670pF.
The only comment that I would make is that overall the IMD3
performance is not what I would like. Another 5 to 6 dB would have
been better.
Harmonics were down 51db for both rigs. I did not test for the spur
on the v4.
Harmonic tests were done with a TinySA connected through a homebrew
50db tap and a step attenuator.
IMD3 tests were done with an RSP1A and the RSP-Spectrum Analyzer
program using the same connections.
At this point, I do not plan to modify my v6 as CW is not a mode I
use. Also, I have other rigs that excel at QRP CW that I would use
instead. So my conclusion is to make the mod IF you want the CW
capability. It does not make sense if you are using SSB.
73
Evan
AC9TU
Links:
------
[1] /g/BITX20/message/87545
[2] /mt/81780486/243852
[3] /g/BITX20/post
[4] /g/BITX20/editsub/243852
[5] /g/BITX20/leave/10189903/243852/952924773/xyzzy
-- Allen/N1ATS/AAR4XG/ECCC
|
Re: Latest from MPJA ,... including Pack of 10- IRF510 N Channel FET Transistor 100V output transistors
From the link, the image on the left is what I saw on the MPJA FETS;
I guess I have some LF power FETs, then.
Bob ¡ª KK5R
On Wednesday, April 14, 2021, 7:22:18 PM EDT, Jerry Gaffke via groups.io <jgaffke@...> wrote:
Bob, I have no idea if the MPJA FET's are legit. I do know that Mouser hasn't had anything but Vishay IRF510's?in the last 10 years. And that my Bitx40 and uBitx both have IRF510's with the Siliconix logo (Vishay owns Siliconix).
And that the bad clone here has an IR logo, the good part has a Siliconix logo: Not clear to me exactly who owns what bits of the old International Rectifier. It seems Vishay bought some of the product lines from IR back in 2007, and that Infineon later bought the rest of IR. The Infineon website has a datasheet for the IRF510, but it's dated 2003: ? ?? Does anybody know if? NFET's? are still being legitimately produced with the IR logo? Jerry, KE7ER
On Wed, Apr 14, 2021 at 02:41 PM, Bob Lunsford wrote:
To help eliminate the guesswork and speculation, I opened up the two packages of URF520's I got from MPJA and found ALL of them were marked IR (International Rectifier) with date code 9-18 (Sept 2018)
?
That doesn't sound generic to me...
?
Bob ¡ª KK5R
?
Hide quoted text
?
On Wednesday, April 14, 2021, 3:35:14 PM EDT, Arv Evans <arvid.evans@...> wrote:
?
?
If building a test jig for evaluation of IRF510 devices, maybe we do not
have to test for actual performance of no-name or other-name devices.
If the test jig were first used to evaluate a known good IRF510, then that
could become the standard to test against when evaluating other IRF510s.?
This decreases the need for expensive standards lab calibration of
test equipment and could speed up the process if many devices were to
be evaluated.
?
Arv
_._
?
On Wed, Apr 14, 2021 at 4:11 AM Shirley Dulcey KE1L < mark@...> wrote:
Vishay bought International Rectifier. The Vishay parts are the direct lineal descendents of the original IRF parts.
Technology has improved a lot since the introduction of IRF510 devices in the early 1980s.? Raw material grading, dhigh resolution handling and laser trimming has
become standard.? IRF has apparently licensed manufacturing of IRF devices to
Samsung and Vishay, and probably several others.? This would seem to indicate
that other manufacturer's clones of the original IRF device may be improved
models.? It would take some highly technical testing to determine if a particular
IRF510 device is as good as the original IRF device, or if it exceeds the quality
of its original design.
?
Large marketing organizations like Digikey or Mouser do not have testing facilities
for determining as-manufactured quality of one source over another.? We have
to trust that they have chosen the best quality and least-cost manufacturers.
?
Some on-line sales outlets are focused on buying and selling of end-of-run
surplus components.? If these items are surplus for space industry or similar
high reliability projects they could be best-in-the-industry.? Or, if they are
surplus from the toy industry they could be worst-of-breed components.?
?
For the IRF510 devices it might be possible to build a decent test jig with
square-wave input, very high frequency scope monitoring, and calibration
to verify test results.? This is probably way beyond the capability of most
of us, and could be expensive to build.? Thoughts in this area are along the
line of using a calibrated and tuned detector at various harmonic frequency
points to see how much of the input harmonic energy is being output, and
at what level.? It gets complicated very quickly.
?
Arv
_._
?
On Tue, Apr 13, 2021 at 10:49 AM Timothy Fidler < engstr@...> wrote: It is worth noting that Hans SUmmers of Qrp Labs will use the Vishay IRF510s and none other. He did a lot of tests before he came to that conclusion.
If you go to him for spare parts for a Qrp Labs kit - that is what he will sell you.? I don't believe he offers them as a? general on line sale part because of his restock costs.?
|
Re: Latest from MPJA ,... including Pack of 10- IRF510 N Channel FET Transistor 100V output transistors
Bob,
I have no idea if the MPJA FET's are legit.
I do know that Mouser hasn't had anything but Vishay IRF510's?in the last 10 years.
And that my Bitx40 and uBitx both have IRF510's with the Siliconix logo (Vishay owns Siliconix).
And that the bad clone here has an IR logo, the good part has a Siliconix logo:
Not clear to me exactly who owns what bits of the old International Rectifier.
It seems Vishay bought some of the product lines from IR back in 2007,
and that Infineon later bought the rest of IR.
The Infineon website has a datasheet for the IRF510, but it's dated 2003:
? ??
Does anybody know if? NFET's? are still being legitimately produced with the IR logo?
Jerry, KE7ER
toggle quoted message
Show quoted text
On Wed, Apr 14, 2021 at 02:41 PM, Bob Lunsford wrote:
To help eliminate the guesswork and speculation, I opened up the two packages of URF520's I got from MPJA and found ALL of them were marked IR (International Rectifier) with date code 9-18 (Sept 2018)
?
That doesn't sound generic to me...
?
Bob ¡ª KK5R
?
Hide quoted text
?
On Wednesday, April 14, 2021, 3:35:14 PM EDT, Arv Evans <arvid.evans@...> wrote:
?
?
If building a test jig for evaluation of IRF510 devices, maybe we do not
have to test for actual performance of no-name or other-name devices.
If the test jig were first used to evaluate a known good IRF510, then that
could become the standard to test against when evaluating other IRF510s.?
This decreases the need for expensive standards lab calibration of
test equipment and could speed up the process if many devices were to
be evaluated.
?
Arv
_._
?
On Wed, Apr 14, 2021 at 4:11 AM Shirley Dulcey KE1L < mark@...> wrote:
Vishay bought International Rectifier. The Vishay parts are the direct lineal descendents of the original IRF parts.
Technology has improved a lot since the introduction of IRF510 devices in the early 1980s.? Raw material grading, dhigh resolution handling and laser trimming has
become standard.? IRF has apparently licensed manufacturing of IRF devices to
Samsung and Vishay, and probably several others.? This would seem to indicate
that other manufacturer's clones of the original IRF device may be improved
models.? It would take some highly technical testing to determine if a particular
IRF510 device is as good as the original IRF device, or if it exceeds the quality
of its original design.
?
Large marketing organizations like Digikey or Mouser do not have testing facilities
for determining as-manufactured quality of one source over another.? We have
to trust that they have chosen the best quality and least-cost manufacturers.
?
Some on-line sales outlets are focused on buying and selling of end-of-run
surplus components.? If these items are surplus for space industry or similar
high reliability projects they could be best-in-the-industry.? Or, if they are
surplus from the toy industry they could be worst-of-breed components.?
?
For the IRF510 devices it might be possible to build a decent test jig with
square-wave input, very high frequency scope monitoring, and calibration
to verify test results.? This is probably way beyond the capability of most
of us, and could be expensive to build.? Thoughts in this area are along the
line of using a calibrated and tuned detector at various harmonic frequency
points to see how much of the input harmonic energy is being output, and
at what level.? It gets complicated very quickly.
?
Arv
_._
?
On Tue, Apr 13, 2021 at 10:49 AM Timothy Fidler < engstr@...> wrote: It is worth noting that Hans SUmmers of Qrp Labs will use the Vishay IRF510s and none other. He did a lot of tests before he came to that conclusion.
If you go to him for spare parts for a Qrp Labs kit - that is what he will sell you.? I don't believe he offers them as a? general on line sale part because of his restock costs.?
|
Re: Latest from MPJA ,... including Pack of 10- IRF510 N Channel FET Transistor 100V output transistors
To help eliminate the guesswork and speculation, I opened up the two packages of URF520's I got from MPJA and found ALL of them were marked IR (International Rectifier) with date code 9-18 (Sept 2018)
That doesn't sound generic to me...
Bob ¡ª KK5R
On Wednesday, April 14, 2021, 3:35:14 PM EDT, Arv Evans <arvid.evans@...> wrote:
If building a test jig for evaluation of IRF510 devices, maybe we do not
have to test for actual performance of no-name or other-name devices. If the test jig were first used to evaluate a known good IRF510, then that
could become the standard to test against when evaluating other IRF510s.?
This decreases the need for expensive standards lab calibration of
test equipment and could speed up the process if many devices were to
be evaluated.
Arv _._
On Wed, Apr 14, 2021 at 4:11 AM Shirley Dulcey KE1L < mark@...> wrote: Vishay bought International Rectifier. The Vishay parts are the direct lineal descendents of the original IRF parts.
Technology has improved a lot since the introduction of IRF510 devices in the early 1980s.? Raw material grading, dhigh resolution handling and laser trimming has
become standard.? IRF has apparently licensed manufacturing of IRF devices to
Samsung and Vishay, and probably several others.? This would seem to indicate
that other manufacturer's clones of the original IRF device may be improved
models.? It would take some highly technical testing to determine if a particular
IRF510 device is as good as the original IRF device, or if it exceeds the quality
of its original design.
Large marketing organizations like Digikey or Mouser do not have testing facilities
for determining as-manufactured quality of one source over another.? We have
to trust that they have chosen the best quality and least-cost manufacturers.
Some on-line sales outlets are focused on buying and selling of end-of-run surplus components.? If these items are surplus for space industry or similar
high reliability projects they could be best-in-the-industry.? Or, if they are
surplus from the toy industry they could be worst-of-breed components.?
For the IRF510 devices it might be possible to build a decent test jig with
square-wave input, very high frequency scope monitoring, and calibration
to verify test results.? This is probably way beyond the capability of most
of us, and could be expensive to build.? Thoughts in this area are along the
line of using a calibrated and tuned detector at various harmonic frequency
points to see how much of the input harmonic energy is being output, and
at what level.? It gets complicated very quickly.
Arv _._
On Tue, Apr 13, 2021 at 10:49 AM Timothy Fidler < engstr@...> wrote: It is worth noting that Hans SUmmers of Qrp Labs will use the Vishay IRF510s and none other. He did a lot of tests before he came to that conclusion.
If you go to him for spare parts for a Qrp Labs kit - that is what he will sell you.? I don't believe he offers them as a? general on line sale part because of his restock costs.?
|
In junior high ( a few decades ago) we had to complete certain projects before we could work on what we wanted to. One was a simple metal chassis with three tube sockets mounted with various wires connecting pins (totally non-functional circuit) and all the wire nicely laced. This was to show we had the necessary skills to do things the right way. That was the one and ONLY time I ever laced wiring. I DON¡¯T feel cheated or anything like that. a few years later I was wiring up a microprocessor¡ no tube sockets in that one.
toggle quoted message
Show quoted text
On Apr 14, 2021, at 11:27 AM, Dennis Zabawa <kg4rul@...> wrote:
I still remember sore fingers from lacing cables with waxed linen cord.
|
Totally agree!
Jack, W8TEE
On Wednesday, April 14, 2021, 3:49:17 PM EDT, Arv Evans <arvid.evans@...> wrote:
Jack
I have followed Dave's work for years, and have even built clones of some
of his projects.? Even with following his work precisely, my own results do
not come close to his precision and appearances.? My conclusion is that
it takes a specific type of artist vision to do that quality of work.? But that
does not mean that we cannot use his work for inspiration and as an
objective for our own builds.? I'm still trying to work up to his standards.
Arv _._
To each, his own.
I find Dave's work beautiful and would make everything I build look as nice if I could.
Jack, W8TEE
On Wednesday, April 14, 2021, 11:33:24 AM EDT, Jerry Gaffke via <jgaffke= [email protected]> wrote:
Squaring off all the wires like that was typical of radios built 100 years ago: ? ?? ? ?? Ten years later stuff got boxed up in a metal chassis to where people never saw the wiring, and so it didn't need to be quite so pretty.? I go for that more modern look. Jerry, KE7ER On Wed, Apr 14, 2021 at 08:13 AM, Jack, W8TEE wrote:
I know what you mean. Most of my kits look like controlled chaos even though you'd think a kit's PCB would make things look pretty good. Then there's the work by Dave Richards, AA7EE, where his Manhattan Style projects are works of art:
--
Jack, W8TEE
--
Jack, W8TEE
|
Jack
I have followed Dave's work for years, and have even built clones of some
of his projects.? Even with following his work precisely, my own results do
not come close to his precision and appearances.? My conclusion is that
it takes a specific type of artist vision to do that quality of work.? But that
does not mean that we cannot use his work for inspiration and as an
objective for our own builds.? I'm still trying to work up to his standards.
Arv _._
To each, his own.
I find Dave's work beautiful and would make everything I build look as nice if I could.
Jack, W8TEE
On Wednesday, April 14, 2021, 11:33:24 AM EDT, Jerry Gaffke via <jgaffke= [email protected]> wrote:
Squaring off all the wires like that was typical of radios built 100 years ago: ? ?? ? ?? Ten years later stuff got boxed up in a metal chassis to where people never saw the wiring, and so it didn't need to be quite so pretty.? I go for that more modern look. Jerry, KE7ER On Wed, Apr 14, 2021 at 08:13 AM, Jack, W8TEE wrote:
I know what you mean. Most of my kits look like controlled chaos even though you'd think a kit's PCB would make things look pretty good. Then there's the work by Dave Richards, AA7EE, where his Manhattan Style projects are works of art:
--
Jack, W8TEE
|
Re: Latest from MPJA ,... including Pack of 10- IRF510 N Channel FET Transistor 100V output transistors
If building a test jig for evaluation of IRF510 devices, maybe we do not
have to test for actual performance of no-name or other-name devices. If the test jig were first used to evaluate a known good IRF510, then that
could become the standard to test against when evaluating other IRF510s.?
This decreases the need for expensive standards lab calibration of
test equipment and could speed up the process if many devices were to
be evaluated.
Arv _._
On Wed, Apr 14, 2021 at 4:11 AM Shirley Dulcey KE1L < mark@...> wrote: Vishay bought International Rectifier. The Vishay parts are the direct lineal descendents of the original IRF parts.
Technology has improved a lot since the introduction of IRF510 devices in the early 1980s.? Raw material grading, dhigh resolution handling and laser trimming has
become standard.? IRF has apparently licensed manufacturing of IRF devices to
Samsung and Vishay, and probably several others.? This would seem to indicate
that other manufacturer's clones of the original IRF device may be improved
models.? It would take some highly technical testing to determine if a particular
IRF510 device is as good as the original IRF device, or if it exceeds the quality
of its original design.
Large marketing organizations like Digikey or Mouser do not have testing facilities
for determining as-manufactured quality of one source over another.? We have
to trust that they have chosen the best quality and least-cost manufacturers.
Some on-line sales outlets are focused on buying and selling of end-of-run surplus components.? If these items are surplus for space industry or similar
high reliability projects they could be best-in-the-industry.? Or, if they are
surplus from the toy industry they could be worst-of-breed components.?
For the IRF510 devices it might be possible to build a decent test jig with
square-wave input, very high frequency scope monitoring, and calibration
to verify test results.? This is probably way beyond the capability of most
of us, and could be expensive to build.? Thoughts in this area are along the
line of using a calibrated and tuned detector at various harmonic frequency
points to see how much of the input harmonic energy is being output, and
at what level.? It gets complicated very quickly.
Arv _._
On Tue, Apr 13, 2021 at 10:49 AM Timothy Fidler < engstr@...> wrote: It is worth noting that Hans SUmmers of Qrp Labs will use the Vishay IRF510s and none other. He did a lot of tests before he came to that conclusion.
If you go to him for spare parts for a Qrp Labs kit - that is what he will sell you.? I don't believe he offers them as a? general on line sale part because of his restock costs.?
|
Farhan, and others
Just finished reading over their group page.? At first glance it appears to
be the work of just two people who possibly work at Virginia Technical
College.? Might even be the basis of a specific class curriculum.? Several
images and documentation seems very close to what is available on
this forum (They do provide a link to this group down near the end of
their page).?
I see their page as valuable for its description of modulation and diode
ring modulators.? Should we reach out to them and offer support and
advice for their group?
Arv _._
On Tue, Apr 13, 2021 at 11:28 PM Ashhar Farhan < farhanbox@...> wrote: Interesting that they don't reach out to us here
An interesting link I discover today :?
73 - Pierre - FK8IH
|
Re: QUESTION - is it possible to get a TX output of CW in A1A?
An answer for everyone!
Thank you all for the answers and for the small scheme that will allow me to add the CW transmission in A1A also in the EASY BITX that I am assembling, without resorting to strange solutions, but simply by moving the BFO in TX to beat 0 with the set frequency ... and at 700/800 Hz from beat 0 in reception!
Thanks again for the help and the confirmation of my expectations.
A cordial greeting to all, 73 de
IW4AJR Loris
|
I still remember sore fingers from lacing cables with waxed linen cord.
|
Re: The "COCORICO UBITX" The French Touch
Hello,
This aftermoon it's was the first "smoke test"... After checking the regulator voltage, I directly connected the arduino (already programmed from the old assembly) and connected the screen Nextion.This first power-up was like the arrival of "Perseverance" on Mars.?Everything is functional on the Nextion at the first attempt.?So I¡¯m pretty proud of my work in my home Nasa. LOLTomorrow, I have to test some quartz and? the different filters.
cdt
|
Re: QUESTION - is it possible to get a TX output of CW in A1A?
Loris
A mixer inherently needs ac signals on 2 ports to produce an output.?
If we inject dc, it can bias the diodes, if enough turning them steadily on, so it can't mix anymore. Ubitx does this, eliminating the mixer function when transmitting cw.?
A small detail, if the stronger LO signal is present but not the weaker RF signal to be mixed, some of the LO signal will leak to the output, as it always does.
There are also simpler mixers using a single diode or transistor, that operate less ideal than the now much more common balanced mixer, that uses 2 or 4 devices.??
Curt
|
Re: Talk: An Evening with Bob Heil K9EID Tuesday 13th April 8 pm BST (which is 1900 UTC)
A recording of the very interesting and indeed entertaining talk by Bob Heil is now available on YouTube:
73
Trystan G0KAY
|
Re: QUESTION - is it possible to get a TX output of CW in A1A?
A keyed audio oscillator can work, but the oscillator and mike amp must feed a clean
sine wave at the correct level into the modulator to get a clean CW signal.
Far simpler to add a resistor from the keyer logic output into a mixer somewhere,
and the results are usually better.
Allard's Bitx40 mods unbalanced the modulator in the way that Loris was asking about.
As I recall, Allard started with a larger resistor on the CW-KEY line.
Some Bitx40 modulators had a weaker response, so he changed the resistor value to 4.7k,
Jerry, KE7ER
toggle quoted message
Show quoted text
On Wed, Apr 14, 2021 at 08:39 AM, Lawrence Galea wrote:
Why not use a keyed audio oscillator with suitable level adjustment at the mic input?
Hide quoted text
?
On Wed, Apr 14, 2021 at 12:14 PM Evan Hand < elhandjr@...> wrote: Loris,
I do not claim to be an expert on mixers.? I am only an amateur at understanding how they work.? Here is what I think would happen.
The DC voltage would be a 0Hz signal that is being added to the BFO frequency which would put the BFO signal on the input to the SSB filter.? So yes to your question.? Biasing the product detector would pass the BFO signal to the SSB filter.? In the ?BITX v6 That would send an 11.056Hz signal to a filter that is designed to pass signals from 11.057MHz to 11.059MHz so there would be a much-reduced signal being sent to the following stages for frequency mixing and amplification.? In a properly adjusted rig that could be as much as 30db to 40db down.
Note that the above BFO and Filter frequencies are approximate for description only.? They would vary depending on the specifics set for the rig under test and the actual SSB filter characteristics.
If the intent is to use it for CW like is done in the first mixer of the ?BITX, then as is done there you would need to adjust the BFO frequency on key down so that it will generate the correct signal to get through the SSB filter, then further adjust one of the later mixers to be on the correct frequency to transmit.
Again, these are my thoughts.? I am open to any comments or corrections.
73
Evan
AC9TU
|
To each, his own.
I find Dave's work beautiful and would make everything I build look as nice if I could.
Jack, W8TEE
On Wednesday, April 14, 2021, 11:33:24 AM EDT, Jerry Gaffke via groups.io <jgaffke@...> wrote:
Squaring off all the wires like that was typical of radios built 100 years ago:
? ??
? ??
Ten years later stuff got boxed up in a metal chassis to where people never saw the wiring,
and so it didn't need to be quite so pretty.? I go for that more modern look.
Jerry, KE7ER
On Wed, Apr 14, 2021 at 08:13 AM, Jack, W8TEE wrote:
I know what you mean. Most of my kits look like controlled chaos even though you'd think a kit's PCB would make things look pretty good. Then there's the work by Dave Richards, AA7EE, where his Manhattan Style projects are works of art:
-- Jack, W8TEE
|
Re: QUESTION - is it possible to get a TX output of CW in A1A?
Why not use a keyed audio oscillator with suitable level adjustment at the mic input?
On Wed, Apr 14, 2021 at 12:14 PM Evan Hand < elhandjr@...> wrote: Loris,
I do not claim to be an expert on mixers.? I am only an amateur at understanding how they work.? Here is what I think would happen.
The DC voltage would be a 0Hz signal that is being added to the BFO frequency which would put the BFO signal on the input to the SSB filter.? So yes to your question.? Biasing the product detector would pass the BFO signal to the SSB filter.? In the ?BITX v6 That would send an 11.056Hz signal to a filter that is designed to pass signals from 11.057MHz to 11.059MHz so there would be a much-reduced signal being sent to the following stages for frequency mixing and amplification.? In a properly adjusted rig that could be as much as 30db to 40db down.
Note that the above BFO and Filter frequencies are approximate for description only.? They would vary depending on the specifics set for the rig under test and the actual SSB filter characteristics.
If the intent is to use it for CW like is done in the first mixer of the ?BITX, then as is done there you would need to adjust the BFO frequency on key down so that it will generate the correct signal to get through the SSB filter, then further adjust one of the later mixers to be on the correct frequency to transmit.
Again, these are my thoughts.? I am open to any comments or corrections.
73
Evan
AC9TU
|
Squaring off all the wires like that was typical of radios built 100 years ago:
? ??
? ??
Ten years later stuff got boxed up in a metal chassis to where people never saw the wiring,
and so it didn't need to be quite so pretty.? I go for that more modern look.
Jerry, KE7ER
toggle quoted message
Show quoted text
On Wed, Apr 14, 2021 at 08:13 AM, Jack, W8TEE wrote:
I know what you mean. Most of my kits look like controlled chaos even though you'd think a kit's PCB would make things look pretty good. Then there's the work by Dave Richards, AA7EE, where his Manhattan Style projects are works of art:
|
Farhan:
I know what you mean. Most of my kits look like controlled chaos even though you'd think a kit's PCB would make things look pretty good. Then there's the work by Dave Richards, AA7EE, where his Manhattan Style projects are works of art:
Visit his web site and you'll find that all his stuff looks like this. Kinda makes me want to pack it all in and take up knitting.
Jack, W8TEE
On Wednesday, April 14, 2021, 10:59:02 AM EDT, Ashhar Farhan <farhanbox@...> wrote:
It is the economy of scale that kicks in with hf signals. It works out to be cheaper than the bill of materials! The way to keep the price under $100 is to build it the ugly way.? You can always scavenge from your junk. I can build an ugly radio in a day, in a pcb, it takes me a week! - f
On Wed 14 Apr, 2021, 4:56 PM Dennis Zabawa, < kg4rul@...> wrote: It seems their BOM totals $190USD.? You can buy a basic kit w/ acrylic front/rear panels and mike, shipped via DHL, for $160USD.? I guess there is a price for education!
--
Jack, W8TEE
|
Bob Lunsford
Loris Bollina
Gerard
Trystan G0KAY