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
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Thanks, Allison.
Jack, W8TEE
On Thursday, October 11, 2018, 1:36:11 PM EDT, ajparent1/KB1GMX <kb1gmx@...> wrote:
STM32F4 series if memory serves.
Allison
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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:
toggle quoted message
Show quoted text
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
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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
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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
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STM32F4 series if memory serves.
Allison
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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
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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
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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
?
?
toggle quoted message
Show quoted text
-----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
toggle quoted message
Show quoted text
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
toggle quoted message
Show quoted text
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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Re: uBITX new Board V4.0-Rev.C
... aha ... that is smart done from Ashar . Also the Raduino-Board now is mounted on the backside of the 25 MHz crystal board , not more inside between space of LCD-Board and 25 MHz board , that means easy plug&play ... Now also the Raduino can easy replaced without something is to unscrew screws ... Thanks , Jens / HB9JOI +++ -----Urspr¨¹ngliche Nachricht----- From: Raj vu2zap Sent: Thursday, October 11, 2018 3:25 PM To: [email protected]Subject: Re: [BITX20] uBITX new Board V4.0-Rev.C 2x2 Jens, Gnd+In and Gnd+Out, add your own filter socket. You will have to disable the stock filter! Raj At 11/10/2018, you wrote: Anybody knows for what is " P3 " connector on the new board ?
(2 x 3 pin , female , located beside left from the12 mHz filter-crystals)
73 , Jens / HB9JOI
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Re: Harmonics and Relay Replacement
About the possession I guess that a non filtered output shows a higher power, which is the sum of the fundamental, the spurs, harmonics and all the garbage left.
Il 11/ott/2018 14:37, "Raj vu2zap" < rajendrakumargg@...> ha scritto:
Relays are sealed, cant use SWR grease. I remember reading in QST some
year April
about how SWR grease makes all the standing waves slip and fall off the
antenna :-))
Most of my testing with harmonics were done on 7.2 or 14.2 Mhz. With
Panasonic relays
the 2rd harmonic shot up by ~20db and the 5th dropped below the -43dbm
green line.
As soon a I get back to the bench I am going to mill off the plastic
around a Panasonic and
see what the construction is. Its height is a little less than the
"Virtual" brand. This should
give us a better understanding or open a new can of worms!
This one of the best groups to learn from, thanks to you guys!
Raj
At 11/10/2018, you wrote:
My guess is that your Panasonic
are possessed by some SWR...
Il 11/ott/2018 13:01, "Raj vu2zap"
<
rajendrakumargg@...> ha scritto:
- Kees,
- My guess is that the contacts being underside are close to the ground
plane of the board and that must be
- helping decreasing the "coupling" of both sets of
contacts.
- Imagine a loop on one side of the relay and another on the other
side.. perfect inductive coupling. The
- Axicom has smaller loops compared to Virtual and others.
- My Panasonic relays made the harmonics worse.. BUT the power out
increased !!! about 20%.
- It's possessed I tell you!
- Raj
- Panasonic relay DS2Y-S-DC12V
- At 11/10/2018, you wrote:
- >Those inductances all look right. Sure would like to know WHY the
Axicom relays have better readings.
|
Something not right 24V PA BITX40
I have my BITX40 up and running. Just got on the air for the first time a month ago. Lots of FT8 contacts and a few other digital contacts. I just put it in a case with a switch for the PA power section.
I can run the PA with the 12 volts or switch to an external source. Before boxing it I was able 13 Watts on 24.5volts. Currently I only get 7 Watts on 24.5 volts.
On 12 volts I get 5.5 Watts with 1.2 amps draw with a loud hello and 97 mA idle
On 24.5 volts I get 7 Watts with 1.5 amp draw with a loud hello and 103 mA idle.
Did I break something or am I doing something wrong? Using Lipo batteries for the PA and they sit idle at 24.5 volts and drop to 24.1 during the transmit. I tried increasing the drive on RV136. Seems I might get more output momentary then it settles back down to 7 Watts.
Any thoughts are appreciated.
|
Re: 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
toggle quoted message
Show quoted text
------ 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
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
|
Jim Sheldon
Jens/HB9JOI