Re: new unbuilt for sale
#ubitx
hi
why is the price more than the $129 of the kit from india
terry gm4dso
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Re: Harmonics and Relay Replacement
Please excuse my incomplete question re advice.
?
I was asking for advice on my original post of Nov.2:??
"I'd appreciate advise on whether the 5303 should work, or whether it was a typo, since it's what I ordered.? The 5303 has a coil power of 200mw, vs. 400mw for the 5403.? See attached data sheet for other factors."
?
... which asked the same question as MVS Sharma on Oct.16:? "I suppose that the prescribed relay was 23105 5403 A201. i see that your relay has 5303 instead. was it a typo? regards sarma vu3zmv
By MVS Sarma ¡¤ #60759 ¡¤ Oct 16"
Neither question elicited responses, so perhaps no one has an opinion.? I haven't installed the 5303 yet.??
-- 73, Al - va3iaw
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Re: ubitx ver. 3 for sale
hi
is it still available and can you ship to uk at what cost
terry gm4dso
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I wanted to see if adding a RF amp to my V4 ubitx would improve reception and see if there were any downsides. I bought the Wideband Amplifier kit from KitsandParts to make this simple. I added the rf amp in the receive path before the mixer. I'm pleased with the increased sensitivity, intermod from other ham stations does not seem to be a problem, and the only issue was some intermod from some local 50KW broadcast stations. Adding a BCI filter in front of the amp solved that problem. My antenna is a end fed long wire for 40-10m. My next step is to add agc to this amp.
Harvey, WA2AAE
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Re: Ideas for homebrew rig for digital modes on VHF/UHF
Thank you for the replies.
I understand that the current digital modes are used on either FM or SSB but I assumed this was largely because that's what most hams had available. Similar to how we ended up with 56k as the fastest modem for dial up because of the limitations of the existing phone system.
I suppose my real question at the moment is what are the advantages and disadvantages of FM vs SSB (or any other form of modulation such as AM or Phase Modulation) for digital work on VHF/UHF?
Perhaps there are no practical difference but I feel this is a good place for me to start my research.
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Re: Ideas for homebrew rig for digital modes on VHF/UHF
FM on the uBITx. Interesting. Not a very popular mode on HF but a good exercise in design anyway. Ill draw something up as a theoretical challenge.
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On Dec 30, 2018, at 8:33 AM, Bill Cromwell <wrcromwell@...> wrote:
Hi,
That won't give the OP the FM mode. But in the Olde Days, prior to 2017, there were many mods publish to add modes to receivers that didn't have them. Mods like a BFO. Mods for a product detector for SSB and improved CW. And lets not forget an FM strip that can be added to the I.F. strip in a receiver. Yes Virginia, there were communication receivers built without BFOs, without product detectors, without FM. What was olde is new again:)
Has anybody done an FM detector for the uBitx or Bitx40? This mail list is for the uBitx and Bitx40 but there ARE other options including the use of transceiving converters. Transverters are transmit additions. At one time transmitters and receivers lived in separate boxes. Some still do. You will want a converter for receive too. Those change the band of operation. Other mods give new modes such as FM such as an FM strip added to a bitx machine. The transmit side will have to be "FMed" too. Not impossible.
73,
Bill KU8H
On 12/30/18 7:12 AM, MadRadioModder wrote:
Ergo, buy a TenTec transverter... or copy one and you are done!
--
bark less - wag more
--
¡_. _._
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Re: Ideas for homebrew rig for digital modes on VHF/UHF
Hi,
That won't give the OP the FM mode. But in the Olde Days, prior to 2017, there were many mods publish to add modes to receivers that didn't have them. Mods like a BFO. Mods for a product detector for SSB and improved CW. And lets not forget an FM strip that can be added to the I.F. strip in a receiver. Yes Virginia, there were communication receivers built without BFOs, without product detectors, without FM. What was olde is new again:)
Has anybody done an FM detector for the uBitx or Bitx40? This mail list is for the uBitx and Bitx40 but there ARE other options including the use of transceiving converters. Transverters are transmit additions. At one time transmitters and receivers lived in separate boxes. Some still do. You will want a converter for receive too. Those change the band of operation. Other mods give new modes such as FM such as an FM strip added to a bitx machine. The transmit side will have to be "FMed" too. Not impossible.
73,
Bill KU8H
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On 12/30/18 7:12 AM, MadRadioModder wrote: Ergo, buy a TenTec transverter... or copy one and you are done!
--
bark less - wag more
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Re: Ideas for homebrew rig for digital modes on VHF/UHF
Ergo, buy a TenTec transverter... or copy one and you are done!
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On Dec 30, 2018, at 5:17 AM, iz oos < and2oosiz2@...> wrote: There is not something else. There are digital modes that are transmitted in FM (dmr, c4fm, dstar, aprs, winlink stuff) and others in SSB (CW, wj, fsk, ft8). In my humble opinion it would be very difficult to implement all these at a reasonable price. I would be interested in a V-U version of the Bitx, that is SSB-CW. A practical solution is to simply add transverters. Some are very cheap on ebay. There are few things to be addressed. First remove spurs on SSB at 28mhz if the transverter does not have a bandpass input filter (TenTec transverter have it) . That can be done with the solution suggested by Farhan. In my opinion the transverters should rely not only to PTT but to the RF sense too in order to be sure you don't fry the transverters. 2m TenTec transverters work FB and have just the RF sense TXRX changeover.
--
¡_. _._
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Re: S-Meter in KD8CEC v 1.1 with Nextion 2.8 does not work
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Re: Ideas for homebrew rig for digital modes on VHF/UHF
There is not something else. There are digital modes that are transmitted in FM (dmr, c4fm, dstar, aprs, winlink stuff) and others in SSB (CW, wj, fsk, ft8). In my humble opinion it would be very difficult to implement all these at a reasonable price. I would be interested in a V-U version of the Bitx, that is SSB-CW. A practical solution is to simply add transverters. Some are very cheap on ebay. There are few things to be addressed. First remove spurs on SSB at 28mhz if the transverter does not have a bandpass input filter (TenTec transverter have it) . That can be done with the solution suggested by Farhan. In my opinion the transverters should rely not only to PTT but to the RF sense too in order to be sure you don't fry the transverters. 2m TenTec transverters work FB and have just the RF sense TXRX changeover.
Il 30/dic/2018 08:49, "FC" < felixc64+groups.io@...> ha scritto: Hello,
I'd like to experiment with digital modes on VHF/UHF and don't want any potential limitation from commercial transceivers that may be available to me.
I have many questions on the topic, but to begin, if I wanted a purpose built rig for digital modes in these bands should I be looking at SSB, FM, or something else?
I also welcome suggestions of other groups or forums where I may be able to find information about this.
Thanks
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Ideas for homebrew rig for digital modes on VHF/UHF
Hello,
I'd like to experiment with digital modes on VHF/UHF and don't want any potential limitation from commercial transceivers that may be available to me.
I have many questions on the topic, but to begin, if I wanted a purpose built rig for digital modes in these bands should I be looking at SSB, FM, or something else?
I also welcome suggestions of other groups or forums where I may be able to find information about this.
Thanks
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Re: Harmonics and Relay Replacement
?Evan, the design is a compromise that has deficiencies that were not originally well recognized.? ?Thanks to some persistent work by some members (I forget all their names but one reallly worked hard at it!)? the dificiencies were recognized.? ?
45 odd years ago my first rig, a Heathkit, had deficiencies.? ?I knew almost nothing, but in the ensuing 6 months I learned a ton of electronics to stop those darned key clicks.? ?And the rig went back and forth to Benton Harbor, which was FAR slower and
more difficult for me than buying something from India? or China is today.? FAR slower.? ?
We all bought this innovative, stripped down, dirt cheap rig from a nearly 3rd world county, amazed at the accomplishment of the designer.? ?I certainly did not expect it to be a Flex.
SO MANY solutions have been published and TESTED? (allison being one of the most prominent teachers in that regard) that it is simply no longer able for me to keep up with them!!!? Pick the one you like that you find proof for.? ?I made extremely simple
measurements using a dummy load and a resistive divider and a secondary communications receiver that indicated an $11 solution with an outboard partial relay box solved the issue of harmonics.? Had I used coax cable, probably would have worked even better!?
Others made even better solutions.? Raj and others have made huge inroads on the spur issue.??
This is a chance for LEARNING and I and many others have profited GREATLY from it.? ?I'm off learning duplexers now, but one should not pass up the opportunity this little gem provides.? ??
Mine has done WINLINK, and ALE, two fascinating techniques I needed it for at the time.? ?It does PSK, WINMOR, ARDOP and would probably even do PACTOR if I conneccted up m pactor modem to it.? ?Just don't overdrive it!? ?I learned how to program for an Arduino
from this little gem and learned the IDE from it.? ?I then built my own Raduino board and started building a SWR system and then tried to build an antenna analyzer --- and learned the difficulites of resistive bridges and how i really needed to understand
some of that better.? ?How much did i pay for all this education?? ?One uBitx.? ?pretty cheap education, huh?? ?The first reading i did on this blog -- ilearned more about mixers than I had ever known in my life.??
You know how much they charged me for that education?? Zero.
you can look at life from up or down, but there are ways to come out on top if you wish.? ?
Cheers!
Gordon Gibby
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OK, I have been following all of the ubitx threads since September, and still do not know what I must do, definitively, to insure that my rig is compliant.? I thought that I had that from this thread, however Ashhar and Raj had different solutions to the
spur issues, with agreement on the relay replacement for harmonics.? On Ubitx.net, Raj's solution is the one given for the spurs.? On the last email go round with? Raj, I was informed that there is still a possible IMD that does not yet have a solution, though
it can be imporved with different biasing and or transistor replacement.
I had planned to run it into a linear, however that is off the table until I know that the spurs and harmonics are not an issue. 10 watts for me (antenna limited by home owners association) is not going to cut it.? I have tried to make contacts on 40m SSB with
limited success.? The current antenna is an OCFD in my attic.? SWR is OK, however I am sure that the effectiveness is limited by the location.? No real choice, as cannot mount it outside (VERY new neighborhood with only young trees, no place to hide).
With the above, my options now become:
1 - dump in the trash and buy a "real" rig (building/solving technical issues is my main reason getting back into the hobby, so not a real option)
2 - Acquire all the tools and skills to insure that the fix really works. (biggest being a SA - $1200+)
Since the most fun of the hobby for me is the building and problem solving, I will be going down option 2.? However if you look at the cost of the SA compared to an Icom IC-7300 (the one I have been looking at) I would be better off from a financial point to
just buy the better rig, even this far into the parts acquisition. .
My point for making this long texted response is that I am not in the norm for the majority of people that would be purchasing this rig as a means to get into the hobby.? Most are bought as an alternative to the high cost rigs because they are on a paper boy
budget (do they still have young people doing paper routes?). What they need is the definitive solution that IF they apply it, then they can be assured it will be legal.? Saying that it is their rig and they need to insure compliance through testing is not
possible for them.? If that is the case for HF Signals, then Ashhar REALLY needs to warn that full testing equipment AND experience are required OR that it can only be built and put on the air under the supervision of someone that can provide that service
(club builds with all fixes included that have been tested by the "Elmer" of the club).
I thought that there was enough testing and verification that we had solutions to the problems.? If that is the case, then HF Signals needs to publish them, on their web page, as the solution that has been verified to fix the issues.? As the provider of the
rig they should have the test equipment and sample size to verify the solution.? What I am asking is that HF Signals steps up to owning the problem and publish how to fix it, including a way to verify.? That or change the advertising to indicate that it is
not a complete solution.
I will apologize now for the rant.? If I get enough emails or comments complaining I will drop off of the board and go my own way.
Evan
AC9TU
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Re: Harmonics and Relay Replacement
Hi Evan,
In the United States it is not the manufacturers who are responsible for your compliance (amateur radio only). It is each licensee responsible for their own compliance. It's not the rule of HF Signals. It's the rules of the FCC.
Licensees in other servoces are also responsible for their own complaince *after* they have purchased type accepted gear. After they have it they are responsible for maintaining it. They rae expected to hire people capable of maintaining compliance (among other things).
Enough about that. Anybody who is discouraged enough to abandon the uBitx they have bought should not toss it into the trash but sell it somebody else to recover part or all of their money. They can put that money toward the cost of a "better" radio. So, no, don't drop your in the trash.
But wait. You said you are interested in problem solving. You don't need an expensive spectrum analyzer to measure those harmonics and spurs (to me harmonics *ARE* spurs). You need an expensive spectrum analyzer to service multiple radios all day long, every day,all week long, every month of every year on a workbench. There are other ways to make those measurements on *one* radio. I would encourage anybody who wants to try it to just do it. You may need some things like step attenuators, reference frequencies and ability to measure very small signals. It is possible to make all of that. But it is also easy to get (easier than even one good SA. There are so many easily available tools now.
Happy New Year and 73,
Bill KU8H
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On 12/29/18 8:13 PM, Evan Hand wrote: OK, I have been following all of the ubitx threads since September, and still do not know what I must do, definitively, to insure that my rig is compliant.? I thought that I had that from this thread, however Ashhar and Raj had different solutions to the spur issues, with agreement on the relay replacement for harmonics.? On Ubitx.net, Raj's solution is the one given for the spurs.? On the last email go round with? Raj, I was informed that there is still a possible IMD that does not yet have a solution, though it can be imporved with different biasing and or transistor replacement.
I had planned to run it into a linear, however that is off the table until I know that the spurs and harmonics are not an issue. 10 watts for me (antenna limited by home owners association) is not going to cut it. I have tried to make contacts on 40m SSB with limited success.? The current antenna is an OCFD in my attic.? SWR is OK, however I am sure that the effectiveness is limited by the location.? No real choice, as cannot mount it outside (VERY new neighborhood with only young trees, no place to hide).
With the above, my options now become:
1 - dump in the trash and buy a "real" rig (building/solving technical issues is my main reason getting back into the hobby, so not a real option)
2 - Acquire all the tools and skills to insure that the fix really works. (biggest being a SA - $1200+)
Since the most fun of the hobby for me is the building and problem solving, I will be going down option 2.? However if you look at the cost of the SA compared to an Icom IC-7300 (the one I have been looking at) I would be better off from a financial point to just buy the better rig, even this far into the parts acquisition. .
My point for making this long texted response is that I am not in the norm for the majority of people that would be purchasing this rig as a means to get into the hobby.? Most are bought as an alternative to the high cost rigs because they are on a paper boy budget (do they still have young people doing paper routes?). What they need is the definitive solution that IF they apply it, then they can be assured it will be legal.? Saying that it is their rig and they need to insure compliance through testing is not possible for them.? If that is the case for HF Signals, then Ashhar REALLY needs to warn that full testing equipment AND experience are required OR that it can only be built and put on the air under the supervision of someone that can provide that service (club builds with all fixes included that have been tested by the "Elmer" of the club).
I thought that there was enough testing and verification that we had solutions to the problems.? If that is the case, then HF Signals needs to publish them, on their web page, as the solution that has been verified to fix the issues.? As the provider of the rig they should have the test equipment and sample size to verify the solution.? What I am asking is that HF Signals steps up to owning the problem and publish how to fix it, including a way to verify.? That or change the advertising to indicate that it is not a complete solution.
I will apologize now for the rant.? If I get enough emails or comments complaining I will drop off of the board and go my own way.
Evan
AC9TU
--
bark less - wag more
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Ed
Well that sounds like ubitx is doing well. Possibly psk31 signals are too scarce. Do compare signals, both pattern and width to w1aw. I am guessing the may be a different modulation scheme. Some types may he identified by the spectrum they use.
As the ubitx firmware only controls the rig, your issue should be unrelated except in a few cases selecting the correct sideband. Rtty requires lsb, usb is mere convention gor other modes to designate dial frequency in some cases.
Curt
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finished UBIXT build CeC v 1.08 firmware.
Problem? FT8 works fine 25? contacts first try
SSB works ok
Psk 31 The only signal I can copy is W1AW bulletin copied at 100%
All other signals I cannot decode. using FLdigi, Digpan, HRD. Worked with audio levels no help.
Is there anything in firmware that would cause this.? Not sure what to do next.
?Ed
N1AHO
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Re: Harmonics and Relay Replacement
OK, I have been following all of the ubitx threads since September, and still do not know what I must do, definitively, to insure that my rig is compliant.? I thought that I had that from this thread, however Ashhar and Raj had different solutions to the spur issues, with agreement on the relay replacement for harmonics.? On Ubitx.net, Raj's solution is the one given for the spurs.? On the last email go round with? Raj, I was informed that there is still a possible IMD that does not yet have a solution, though it can be imporved with different biasing and or transistor replacement.
I had planned to run it into a linear, however that is off the table until I know that the spurs and harmonics are not an issue. 10 watts for me (antenna limited by home owners association) is not going to cut it.? I have tried to make contacts on 40m SSB with limited success.? The current antenna is an OCFD in my attic.? SWR is OK, however I am sure that the effectiveness is limited by the location.? No real choice, as cannot mount it outside (VERY new neighborhood with only young trees, no place to hide).
With the above, my options now become:
1 - dump in the trash and buy a "real" rig (building/solving technical issues is my main reason getting back into the hobby, so not a real option)
2 - Acquire all the tools and skills to insure that the fix really works. (biggest being a SA - $1200+)
Since the most fun of the hobby for me is the building and problem solving, I will be going down option 2.? However if you look at the cost of the SA compared to an Icom IC-7300 (the one I have been looking at) I would be better off from a financial point to just buy the better rig, even this far into the parts acquisition. .
My point for making this long texted response is that I am not in the norm for the majority of people that would be purchasing this rig as a means to get into the hobby.? Most are bought as an alternative to the high cost rigs because they are on a paper boy budget (do they still have young people doing paper routes?). What they need is the definitive solution that IF they apply it, then they can be assured it will be legal.? Saying that it is their rig and they need to insure compliance through testing is not possible for them.? If that is the case for HF Signals, then Ashhar REALLY needs to warn that full testing equipment AND experience are required OR that it can only be built and put on the air under the supervision of someone that can provide that service (club builds with all fixes included that have been tested by the "Elmer" of the club).
I thought that there was enough testing and verification that we had solutions to the problems.? If that is the case, then HF Signals needs to publish them, on their web page, as the solution that has been verified to fix the issues.? As the provider of the rig they should have the test equipment and sample size to verify the solution.? What I am asking is that HF Signals steps up to owning the problem and publish how to fix it, including a way to verify.? That or change the advertising to indicate that it is not a complete solution.
I will apologize now for the rant.? If I get enough emails or comments complaining I will drop off of the board and go my own way.
Evan
AC9TU
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Re: Harmonics and Relay Replacement
The relays are on the other side of the board?
Bob ¡ª KK5R
--------------------------------------------
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On Sat, 12/29/18, ajparent1/KB1GMX <kb1gmx@...> wrote: Subject: Re: [BITX20] Harmonics and Relay Replacement To: [email protected] Date: Saturday, December 29, 2018, 5:54 PM On Sat, Dec 29, 2018 at 01:21 PM, Bob Lunsford wrote: I had a sudden thought... It does happen. >>>Considering Allison's wrapping the relays to get some isolation, if the relays are somewhat mirror-image connection-wise, what about merely mounting the relays on the other side of the board? This would give some isolation because of he ground plane of the board and some lower risk of feeding the wrong signal to the wrong location merely because of the distance increase.<<< IT may help but if you really read everything.? ?The problem becomes obvious? once the relays are out of the way.?? I repost the picture from the wiki... Fix that and things get better.? Allison
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Re: Harmonics and Relay Replacement
Well, the work you guys are doing is incredible. In it¡¯s difficulty I mean. ? It was much easier just to add a daughter board with the right sided relays! ?Minutes. ?
On Dec 29, 2018, at 17:54, ajparent1/KB1GMX < kb1gmx@...> wrote:
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On Sat, Dec 29, 2018 at 01:21 PM, Bob Lunsford wrote:
I had a sudden thought... It does happen.
>>>Considering Allison's wrapping the relays to get some isolation,
if the relays are somewhat mirror-image connection-wise, what
about merely mounting the relays on the other side of the board?
This would give some isolation because of he ground plane of
the board and some lower risk of feeding the wrong signal to the
wrong location merely because of the distance increase.<<<
IT may help but if you really read everything.? ?The problem becomes obvious?
once the relays are out of the way.??
I repost the picture from the wiki...
Fix that and things get better.?
Allison
<1714.jpeg>
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Re: Harmonics and Relay Replacement
Yes, the board placement and routing could be better. Design should be improved on v5. Allison has spent months poking at uBitx's, and making careful measurements. I have not. I am curious what she sees with a stock uBitx, KT1,2,3 replaced with Axicom, no sockets. Allison wrote: ... and Kees S21 show it,? the rising tail as frequency is increased showing?the frequency dependent coupling. Can you tell me where to find that? A search for "Kees S21" or "K5BCQ S21" mostly just finds your last post. If 20,40 and 80 are clean, that's good enough for me on a $129 transceiver. It may be years before most of us find reason to venture above 20m. Looking back through this thread, I see many examples of measurements that find the Axicom relays bring the uBitx harmonics into compliance with US regs at -43dBc. Here's a few examples: ? ?? /g/BITX20/message/60371? ?? /g/BITX20/message/61018? ?? /g/BITX20/message/60980As Raj notes, they do have to be seated flat on the board, no sockets. I can believe that some fail to come into compliance. Could be a different flavor of Axicom relay, different installation of the relay, other mods already hacked into the board, drive level, IRF510 quiescent current, supply voltage, a different method of doing measurements, different frequencies within each band, and who knows what else. It's complicated. On a QRP rig, close to -43dBc is close enough for most (but not all) of us. At that point, harmonics on a 10W rig are down around 1/2 of a milliWatt. On a compliant 1kW rig, the harmonics might be as much as 50 milliWatts. If you want better than what the Axicom relays do, then running coax from the uBitx final to some external box with LPF's is an option.? Or perhaps one of the other LPF hacks to the uBitx board described in the forum.?? Next up: spur fix. If Raj's L5,L7 replacement fix works well enough, that seems ideal (simple). I'd probably try that first. Be sure to use the specific shielded parts he recommends,? standard issue surface mount inductors don't help. Farhan's LPF where the 45mhz IF goes into the D1,D2 mixer looks good as well. There has not been a lot of talk here about a 12mhz spur, but Farhan's 12mhz trap and hack to the 45mhz IF amp is worth looking into if it is an issue. Jerry, KE7ER
On Sat, Dec 29, 2018 at 01:08 PM, ajparent1/KB1GMX wrote:
Short and simple, its a mess.?
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Re: Harmonics and Relay Replacement
On Sat, Dec 29, 2018 at 01:21 PM, Bob Lunsford wrote:
I had a sudden thought... It does happen.
>>>Considering Allison's wrapping the relays to get some isolation,
if the relays are somewhat mirror-image connection-wise, what
about merely mounting the relays on the other side of the board?
This would give some isolation because of he ground plane of
the board and some lower risk of feeding the wrong signal to the
wrong location merely because of the distance increase.<<<
IT may help but if you really read everything.? ?The problem becomes obvious?
once the relays are out of the way.??
I repost the picture from the wiki...
Fix that and things get better.?
Allison
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MadRadioModder
Bob Lunsford
