Re: digital mode BITX QSO Afternoon/Evening, Sunday, October, 14 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
?[grin]? ?except the ORIGINAL digital mode:? CW
cheers
gordon
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From: [email protected] <[email protected]> on behalf of K5ESS <k5ess.nothdurft@...>
Sent: Thursday, October 11, 2018 4:34 PM
To: [email protected]
Subject: Re: [BITX20] digital mode BITX QSO Afternoon/Evening, Sunday, October, 14 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
?
Digital modes not allowed on 7277. ?FCC 97.305
Mike
K5ESS
?
From: [email protected] [mailto:[email protected]]
On Behalf Of Don - KM4UDX
Sent: Thursday, October 11, 2018 1:22 PM
To: [email protected]
Subject: [BITX20] digital mode BITX QSO Afternoon/Evening, Sunday, October, 14 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
?
I gave phone/SSB a go last sunday from Northern Virginia, no luck.
I have much better luck with PSK31 or JT8.?
Does any uBITXer want to try digital modes on 10/15??
If so, I'd vote for staying on the same 7277 but use psk31 just for fun?
Don
km4udx
|
Re: digital mode BITX QSO Afternoon/Evening, Sunday, October, 14 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
Digital modes not allowed on 7277. ?FCC 97.305 Mike K5ESS ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Don - KM4UDX
Sent: Thursday, October 11, 2018 1:22 PM
To: [email protected]
Subject: [BITX20] digital mode BITX QSO Afternoon/Evening, Sunday, October, 14 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere. ? I gave phone/SSB a go last sunday from Northern Virginia, no luck.
I have much better luck with PSK31 or JT8.?
Does any uBITXer want to try digital modes on 10/15??
If so, I'd vote for staying on the same 7277 but use psk31 just for fun?
Don
km4udx
|
YEP !? Misstyped.... ------------------------------- On 10/11/2018 16:37, ajparent1/KB1GMX wrote: On Thu, Oct 11, 2018 at 04:04 AM, Woody wrote:
Already have new 680 uh inductors on order, not relays (yet).
Don't you mean 680nh?? Its only a factor of 1000 difference between nH and uH.
Allison
--
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Re: QSX 10W HF Linear PA kit
Allison,
concerning the "stuff" coming out of the first mixer passing
through the input lpf and reaching Q90: this gives me the hint
that the lpf does not problerly do what it should!
Did You make a measurement on the mirror reception which should
be attenuated by the input lpf? Or is it another stone to be
lifted?
In transmit mode the carrier leak should also be attenuated by
this lpf. BUT: in transmit mode there is also the sum of IF + VFO
of assumingly nearly? the same amplitude (in theory exactly the
same amplitude) as the wanted signal, which is reflected back into
the mixer-- probably producing more unwanted products wiothin the
mixer.
My idea is to use a diplexer (lpf - hpf the latter terminated
into 50 ohms, cross over frequency somewhere between 30 and 45
MHz)? and a three transistor "original W7ZOI design" amp (but with
BFR106 gain set to 15 dB) instead of the singe Q90.? Then another
stage --hm 2N5109 may be a good choice as You already stated.
One more thing which pussels me:
in the QRP-labs PA : the output stage fo the driver is using a
center tapped transformer. Why not choose an extra bifilar wound
choke as correctly done int the PA stage?? Did You try this
configuration?
Henning
Am 11.10.2018 um 21:18 schrieb
ajparent1/KB1GMX:
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Henning,
If you use Q90 you only need maybe 13-15db with headroom.
I'll make a comment.? BANDPASS the output of Q90, there is way too
much stuff coming
out that can even if it meets -43dbc down contribute to IMD and
stuff.? What I've seen
going into?Q90 was already dirty and had poor IMD, carrier
leakage.? If you don't then
worrying the IMD is pointless.
Hint: for building.? Get a small cone shaped Carborundum stone to
round the edges of the
FB61/43-2402 balun cores as they tend to have very sharp edges and
tends to scrape off
the enamel causes inter-turn shorts.? I use a Dremel (motor tool)
branded stone with
fingers for that.
IMD, D3 and D5 not fully tested yet.? I expect it will be close to
many of the 12V systems that
aren't burning current for running class A.? ?Then again if the
source and driver stages one
builds are not good your not going to get performance.? ?Grafted
to ubitx, why worry what
you get will be what you put in.
The 1db compression is at 13.8V is? 14-15W, moves up with voltage
to over 20W at 20V.? ?
That was with 125ma idle per-device.? ? Sweet spot on two was at
160ma each.
I have a few more to build and test for comparison and then get to
deeper testing.
Its a pleasure working with an amp that is bullet proof stable.
The RD16 does not need 500ma, unless your shooting for class A!?
more like 200-250 per device and
it also depends on Push-pull (lower) and single ended (higher).
In both cases IMD and idle current are connected to a point.
uBitx is IMD limits are low due to drive and other internal issues
before the amp.
My plan is using it with a modded Atlas 210X to replace the 100W
amp with
a QRPlabs amp plus driver.? The driver for that will be a MPS6514,
2n5109,
2n3545(ALC) and I expect at 10W about the same specs (IMD,
carrier,
harmonics) as the original radio.? The other mods include
replacing the
whole analog VFO with a digital VFO system.
Allison
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Re: QSX 10W HF Linear PA kit
Henning,
If you use Q90 you only need maybe 13-15db with headroom.
I'll make a comment.? BANDPASS the output of Q90, there is way too much stuff coming
out that can even if it meets -43dbc down contribute to IMD and stuff.? What I've seen
going into?Q90 was already dirty and had poor IMD, carrier leakage.? If you don't then
worrying the IMD is pointless.
Hint: for building.? Get a small cone shaped Carborundum stone to round the edges of the
FB61/43-2402 balun cores as they tend to have very sharp edges and tends to scrape off
the enamel causes inter-turn shorts.? I use a Dremel (motor tool) branded stone with
fingers for that.
IMD, D3 and D5 not fully tested yet.? I expect it will be close to many of the 12V systems that
aren't burning current for running class A.? ?Then again if the source and driver stages one
builds are not good your not going to get performance.? ?Grafted to ubitx, why worry what
you get will be what you put in.
The 1db compression is at 13.8V is? 14-15W, moves up with voltage to over 20W at 20V.? ?
That was with 125ma idle per-device.? ? Sweet spot on two was at 160ma each.
I have a few more to build and test for comparison and then get to deeper testing.
Its a pleasure working with an amp that is bullet proof stable.
The RD16 does not need 500ma, unless your shooting for class A!? more like 200-250 per device and
it also depends on Push-pull (lower) and single ended (higher).
In both cases IMD and idle current are connected to a point.
uBitx is IMD limits are low due to drive and other internal issues before the amp.
My plan is using it with a modded Atlas 210X to replace the 100W amp with
a QRPlabs amp plus driver.? The driver for that will be a MPS6514, 2n5109,
2n3545(ALC) and I expect at 10W about the same specs (IMD, carrier,
harmonics) as the original radio.? The other mods include replacing the
whole analog VFO with a digital VFO system.
Allison
|
digital mode BITX QSO Afternoon/Evening, Sunday, October, 14 3PM & 7PM Local Time, 7277 kHz in North America, 7177 kHz elsewhere.
I gave phone/SSB a go last sunday from Northern Virginia, no luck.
I have much better luck with PSK31 or JT8.?
Does any uBITXer want to try digital modes on 10/15??
If so, I'd vote for staying on the same 7277 but use psk31 just for fun?
Don
km4udx
|
Thanks, Allison.
Jack, W8TEE
On Thursday, October 11, 2018, 1:36:11 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:
STM32F4 series if memory serves.
Allison
|
Allison, This is a plot with a 680nH inductor in series with one side of the coil and relay armature. Note the self resonance is now off to the right beyond the 100Mhz scan width and that the plot is about 12dB worse than the one using a 100uH inductor.? My Mouser inductor order should be here today. As I said before I have no idea what happens if you add these inductors to ALL the relay coils (2 per) on a LPF board, but I have the boards ready to test with the appropriate inductor pads. The idea is to reduce the coupling between the RF on the active relay armature and the relay coil and to other relay coils and their armatures.? 73 Kees K5BCQ ?  sf
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Re: QSX 10W HF Linear PA kit
Allison,
I totally agree,? my post was just thinking for the stage after
Q90 or its better verison. My guess is that the BFR90 or as You
already mentioned these small signal transitors are not good
enough for "higer" powers.
One th9ing I really like of the IRF510 Pa is the lower quiescent
current: compared to the RD16HFF1 (aboput 500 mA per Transistor)
the IRF510 only draws 200 mA !
BTW:? on Hans?instruction paper I am missing the performance data
on the 1 dB compression point and of course the IMD behaviour (d3,
d5 etc). do You have these numbers?
My kit is shipped so I am anxious to build my unit and test!
Henning
DK5LV
? ?
Am 11.10.2018 um 19:39 schrieb
ajparent1/KB1GMX:
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On Tue, Oct 9, 2018 at 07:54 AM, Henning Weddig wrote:
oncerning the UBITX: the PA delivers 26 dB of gain, so for 10 W
output the input power for the PA is +40 dBm - 26 dB = +14 dBm
This power can be easily achieved with only one MMIC e.g. one of
the GALI amps--- or a discrete verions (BS170)?
You need more gain than that from the mixer to output.? About 30db
to 36db.? Also the driver need to deliver +14dbm but I'd
strongly suggest enough headroom to hit 20dbm.? You want to hit
10W but not have a stage limiting at 10W.
Allison
|
Re: QSX 10W HF Linear PA kit
timmy,
Your not even close.? The Funster (a CW rig) topology is to drive a class C final for CW
so linearity is not even considered.? So that is outside the conversation as usual.
The drive needed is about 25-80mW.??
I do agree MMICs are not needed and two good transistors capable of delivering a max
of 100mW in the 1-30mhz range will be more than adequate.
Allison
|
Re: QSX 10W HF Linear PA kit
On Tue, Oct 9, 2018 at 07:54 AM, Henning Weddig wrote:
oncerning the UBITX: the PA delivers 26 dB of gain, so for 10 W output the input power for the PA is +40 dBm - 26 dB = +14 dBm This power can be easily achieved with only one MMIC e.g. one of the GALI amps--- or a discrete verions (BS170)?
You need more gain than that from the mixer to output.? About 30db to 36db.? Also the driver need to deliver +14dbm but I'd
strongly suggest enough headroom to hit 20dbm.? You want to hit 10W but not have a stage limiting at 10W.
Allison
|
STM32F4 series if memory serves.
Allison
|
Re: Harmonics and Relay Replacement
Thanks Gary!
I had not thought to try mounting them on the bottom of the board so there would be a ground plane shield between the relay and other wiring. ?I just did that and ran the tests again. ?Unfortunately they were NOT encouraging.?
The only improvement was the 40 meter third harmonic. ?In all other cases, both the 2nd and 3rd harmonics were worse with the relays on the bottom rather than the top of the uBITX main board. ?They did, however remain in spec with the worst case being the 3rd harmonic of 40 meters. This one was marginally better on the bottom but none of the others benefitted from the change.
Results with the relays on the bottom of the board vs on the top. ?Same uBITX used for the original tests, I just carefully moved the relays to the bottom. ?Not going to move them again, but will put the new relays back on top of the 2nd V4 board later today.
Jim Sheldon, W0EB
80 meters? 2nd harmonic ?-62.1 dBC ?vs -65.7 dBC - bottom worse 3rd harmonic -58.4 dBC vs -76.4 dBC ?- bottom worse
30 meters - not tested today
40 meters? 2nd harmonic -56.2 dBC vs ?-58.0 dBC - bottom worse 3rd harmonic -51.7 dBC vs -47.2 dBC - bottom better
20 meters 2nd harmonic - 57.5 dBC vs -65.2 dBC - bottom worse 3rd harmonic - -52.6 dBC vs -64.8 dBC - bottom worse
17 meters not tested yesterday so not tested with relays on top of the board. 2nd harmonic -53.1 dBC 3rd harmonic -61 dBC ??
------ Original Message ------
Sent: 10/11/2018 9:34:14 AM
Subject: Re: [BITX20] Harmonics and Relay Replacement
Hi Jim,
Just wanting to lob out an idea for consideration on your multiple uBITX board relay experiment, if it is still in progress.
Mounting the Axicom relays from the back side, where they are directly over a mostly ground plane.
Experiment split to see if it further improves / or addresses your 40m question.
Thanks for the work / effort.
Rgds,
Gary
AG5TX
|
Re: Harmonics and Relay Replacement
Scott, Use the shortest leads possible, measure the inductance as quickly as you can after "Zeroing" your meter with the leads shorted. ?That's the way I do it. ?The inductance of the leads is a factor as well as the capacitance of your hand & fingers. ?Zero it, connect the inductor and get your hands back. ?Write down the reading as quick as you can. ?I also turn the unit on and leave it on for at least 10-15 minutes before doing any measurements with it. ?This applies to any LC meter, no matter the brand or the circuit it uses.
About the best advice I can give, ?maybe Raj does it differently and he will chime in also.
Jim - W0EB
------ Original Message ------
From: "Scott McDonald via Groups.Io" < ka9p@...> Sent: 10/11/2018 10:46:44 AM
Subject: Re: [BITX20] Harmonics and Relay Replacement
Hi Jim, or Raj, or ¡.
?
I have trouble with reproducibility on lower numbers with my recently purchased LC200.
?
Butt when I see people that know what they are doing having good results, I'm inclined to ask whether there is anything special, or for that matter, just how are you measuring the lower value inductances, figuring based on past experience that I may not have yet acquired the "knack."
?
Thanks, Scott ka9p
?
?
-----Original Message-----
From: Jim Sheldon < w0eb@...>
To: BITX20 < [email protected]>
Sent: Thu, Oct 11, 2018 9:37 am
Subject: Re: [BITX20] Harmonics and Relay Replacement
Hi Raj,
Funny, I have a DE-5000, LC-100A (real cheap one from eBay) and the AADE
and they all agree within less than 1 percent. You might have a bad
crystal oscillator on the uP in your AADE? Or maybe I just got lucky as
I was given my AADE by a friend, several years ago. Not sure where he
got it.
The biggest surprise is how accurate the very inexpensive LC-100A has
been. I think I paid $9.95 USD with free shipping for it.
Jim, W0EB
------ Original Message ------
From: "Raj vu2zap" < rajendrakumargg@...>
To: [email protected]
Sent: 10/11/2018 3:45:22 AM
Subject: Re: [BITX20] Harmonics and Relay Replacement
>I don't trust my AADE meter below 1uH. I use a meter called DE 5000, it
>read commercial
>sub uH inductors very accurately. The AADE meter was way off.
>
>The DE meter can be set for 1,10,100 KHz measurement frequency. At 100K
>the meter
>reads 1nH
>
>Raj
>
>
>You will need the accesories TL-21 and 22 ..
>
>At 11/10/2018, you wrote:
>>Kees,
>>In measuring a Virtual relay and an Axicom relay that I have here,
>>both show approximately 20nH.
>
>
>
>
|
Allison,
It's 680uH which is the largest I found which will handle the relay current and has a self resonance around 2MHz. I tried 100nH and didn't see much difference. The 680nH parts have a self resonance around 135 MHz and I'll see if I can dig one of those up somewhere.
73 Kees K5BCQ
|
On Thu, Oct 11, 2018 at 04:04 AM, Woody wrote:
Already have new 680 uh inductors on order, not relays (yet).
Don't you mean 680nh?? Its only a factor of 1000 difference between nH and uH.
Allison
|
Re: Harmonics and Relay Replacement
Hi Jim, or Raj, or ¡.
?
I have trouble with reproducibility on lower numbers with my recently purchased LC200.
?
Butt when I see people that know what they are doing having good results, I'm inclined to ask whether there is anything special, or for that matter, just how are you measuring the lower value inductances, figuring based on past experience that I may not have yet acquired the "knack."
?
Thanks, Scott ka9p
?
?
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-----Original Message-----
From: Jim Sheldon <w0eb@...>
To: BITX20 < [email protected]>
Sent: Thu, Oct 11, 2018 9:37 am
Subject: Re: [BITX20] Harmonics and Relay Replacement
Hi Raj,
Funny, I have a DE-5000, LC-100A (real cheap one from eBay) and the AADE
and they all agree within less than 1 percent. You might have a bad
crystal oscillator on the uP in your AADE? Or maybe I just got lucky as
I was given my AADE by a friend, several years ago. Not sure where he
got it.
The biggest surprise is how accurate the very inexpensive LC-100A has
been. I think I paid $9.95 USD with free shipping for it.
Jim, W0EB
------ Original Message ------
From: "Raj vu2zap" < rajendrakumargg@...>
To: [email protected]
Sent: 10/11/2018 3:45:22 AM
Subject: Re: [BITX20] Harmonics and Relay Replacement
>I don't trust my AADE meter below 1uH. I use a meter called DE 5000, it
>read commercial
>sub uH inductors very accurately. The AADE meter was way off.
>
>The DE meter can be set for 1,10,100 KHz measurement frequency. At 100K
>the meter
>reads 1nH
>
>Raj
>
>
>You will need the accesories TL-21 and 22 ..
>
>At 11/10/2018, you wrote:
>>Kees,
>>In measuring a Virtual relay and an Axicom relay that I have here,
>>both show approximately 20nH.
>
>
>
>
|
Re: Harmonics and Relay Replacement
Mike,
You asked about the two LPF filters. Here they are pictures and plots. The components used on the small board and the large board are the same and they are both at about 10MHz (same filter design as used on the uBITX but these use Mica caps and T-37 toroids. Using the existing capacitors and toroids off the uBITX board gives nearly the SAME results. The larger board is made from a proto board with squares on one side and a ground plane on the other.?
The last plot shows one of the QRP Labs boards at a slightly different frequency.
73 Kees K5BCQ
?
#1 shows the "Gold" LPF with quality short leads and the small LPF board with quality short leads.
#2 shows the "Gold" LPF plot
#3 shows the small LPF board plot. This is your NO5K built board with the same components and the one you have a picture of on your SA with MUCH better results ??
#4 is one of Hans' small QRP Labs boards (slightly different frequency.
?
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Re: Harmonics and Relay Replacement
Amazon has the meter and accessories for $119.97. I¡¯ll be picking up that meter off your recommendation.
Joe
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On Oct 11, 2018, at 4:45 AM, Raj vu2zap <rajendrakumargg@...> wrote:
I don't trust my AADE meter below 1uH. I use a meter called DE 5000, it read commercial
sub uH inductors very accurately. The AADE meter was way off.
The DE meter can be set for 1,10,100 KHz measurement frequency. At 100K the meter
reads 1nH
Raj
You will need the accesories TL-21 and 22 ..
At 11/10/2018, you wrote:
Kees,
In measuring a Virtual relay and an Axicom relay that I have here, both show approximately 20nH.
|
Re: Purchase of uBitx on hold until?
Wow wow. Okay no wonder I couldn¡¯t hear myself too well on websdrs after the mod. I thought it was just band conditions. I¡¯ll order those coils ASAP!! Thanks Raj for your knowledge as always
Joe
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On Oct 11, 2018, at 3:40 AM, Raj vu2zap <rajendrakumargg@...> wrote:
Joe,
With 45MHz filter you may lose up to half the power. With SMD I get like 95% of stock.
Raj
At 11/10/2018, you wrote:
Are you saying that the second 45mhz mod can be removed from the TX with this mod? How much power loss is lost with the 45mhz is in place?
Nice work by the way. I¡¯d like to try this for sure.
Joe
PS wheres Allison been? She must be on vacation.
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Jim Sheldon