raduino connections on bitx40
hi the wire up instructions talk about the top side and the bottom side but which is top and which is bottom
it says to connect the 5 pin to the bottom side - is that the 16 pin connections and if it is which end are the 5 pins to connect
i am confused
terry gm4dso
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Re: 2N2222A vs 2N3904 sourcing
Ralph yes right here about 6 wweeks ago.
We repeat everything here at at least 5 times.? Sometimes more.
Allison
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Re: 2N2222A vs 2N3904 sourcing
Yes!
and over 200 posting about it.
And no forcing 3904s to marginal gain.? Throw the damn things out.? If you want
to use them do it right rather than struggling.? First 5 stages at low gain, its all the?
3904 can do 10-11db as you still need about 60db gain over all.
The goal then was flat 10W, at the point where spurs and? hunting other illnesses
took over I was at 12W at 80 and 6-7W at 10M.
Then I noticed at 28mhz we are barely 30db down for the 17mhz spur!? At that
point a useful and functional 10m capability was a waste of effort.
Then there is the carrier leak... and the lowpass filter failure.
Allison
?
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Re: uBITX Firmware CEC Version 1.1 Release
#ubitx
Tom
Uploading any firmware through Xloader will not damage the boot area on Arduino Nano.?Check if the serial port is recognized normally.
Also check that CAT communication is being performed.
If your Nano is damaged, it is recommended to use the ICSP tool and the Arduino IDE.
Ian
I downloaded V1.1 and XLOADED the 16P version it to my uBITX V3.? All I have now is a top line of boxes on my standard isssue display and XLOADER will no longer work in order to re-install V1.061.? Any suggestions?
Tom
-- Best 73 KD8CEC / Ph.D ian lee kd8cec@...
(my blog)
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re prev message , PM,? on suggestion of diode switch of BPF element. Using a? ?BAT 592 PIN diode is better than trying to press a small sig diode into duty.? If you cannot source this part then look at parts anchor-electronics of Santa Clara (mail order)? has for sale. Look at diodes on his PDF? and look for one he calls antenna switching diode. I am assuming you are in the US.
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hi all
bitx40 has arrived so watch this space
first job is get it going as delivered
next see if i can get it onto 80
thanks Allard for info on sketch
terry
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Re: K5BCQ uBITX Relay Switched LPF/BPF board
Hello Kees, ? Please count me for one complete kit and relays 6xLPF 73¡¯s de Jacques ¨C F1APY ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Kees T
Sent: Thursday, September 13, 2018 8:50 PM
To: [email protected]
Subject: Re: [BITX20] K5BCQ uBITX Relay Switched LPF/BPF board ? Yes, on the 6x LPF stuff. Hope it's a more restrained than the AGC/Click mini-kit ordering.
I just posted the early LPF order status as "K5BCQ LPF Kit Orders" in the uBITX files section under my call.?
73 Kees K5BCQ
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Re: K5BCQ uBITX Relay Switched LPF/BPF board
Kees
If this kit is still available, happy to pay the asking $30 + 4 for shipment to 01886 in MA.
Kindly let me know availability, and if so how you would like to receive payment (PayPal, check, MO .....)
73 de kc1ccr
bammi
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Re: 2N2222A vs 2N3904 sourcing
LOOK at the picture, please ... Thats WHY I labeled EVERYTHING I could think of ...-27DB input ..O DB output Frequency LABEL across bottom ...I agree that you will NEVER get flat gain in the PA "as configured" ...Ever hear of "emitter bypassing: hint that CAPICITOR in the emitter does the trick .... Btw I breadboarded Q90 and Q912 ...Put a socket so I could SWAP transistors and was NOT able to reproduce your claims about FT ...The ONLY transistor that reacted was one with an FT on 15 mhz...The circuit (on MY bench at least) is being dominated by the lack of emitter capicitor bypassing and by inductance of the transformers ...NOT by any "ft" cruft ...Nor by Current ..again I refer to the figure in EMRFD mentioned in my previous post ...PS every STAGE in that pa is or should be operated as CLASS A ... Just to be clear ...-5 @ 0 Mhz ...-1 @ 10 Mhz...-1 @ 15 Mhz ....-4 @ 20 Mhz ...-5 @ 25 Mhz...-6 @ 30 Mhz... -8 @ 35 Mhz...-9 @ 40 Mhz ?
Not FLAT ...But a whole lot better than I've seen anywhere else in this group ...Can YOU do as well (hopefully better)
Jim
?
On Thursday, September 13, 2018, 6:59:26 PM PDT, ajparent1/KB1GMX <kb1gmx@...> wrote:
On Thu, Sep 13, 2018 at 06:24 PM, Jim Tibbits wrote:
nearly flat across the passband (10 meters is about 5-6 db down)
Jim,
Is it flat or does it fade by 5-6db at the 10m end?? ?Seems a contradiction.
BTW what output power are you getting.? For the drivers it needs to be a half watt (27dbm).
for the predrivers it will be the stage gain less but likely 50 or more mW (17dbm).
Even q90 has to be good to maybe 3-5mW (about 7dbm).? ?I say this as small
signal performance is not always a predictor of high power behavior.? And
since the amp has a serious IMD problems over 2W some stages are
collectively?are?running short.
The amps pass band for the amp is 3.5mhz to 29.99 Its anything but flat.
As there are many (all) that are not flat as in well over 12W at 80m and maybe 2W
at 10m.? IF it were flat to 3db it would be 6W at 10M not 2w.
This is what I've been saying for months.? The only way to get flat from 3-10mhz with 3904s
is dial the stage gain down to maybe 11DB.? The only problem with with all four stages
weighing in at under 43-45 DB total your well below what is required to? get 10W out
from the last mixer to the antenna.? FYI the mixer output at -17dbm is dirty so its not
a good idea to push for more.? Last I checked from -17 to +40dbm is a mere 57db of gain.
You might get 10W if each stage averages 14.4db across the full band width.
Your SA proves that is not going to happen.? Getting 11db and flat is possible
but you run out of gain and there is no physical place to add a stage.
The part does not have the FT and the Gain/bandwidth product to do that.
It also has a gain(hfe) that decreases with collector current.? At full power the
collector current is NOT 20ma. ( I'd expect about 42 to 45ma per transistor).
The exception for that would be q90 as its true class A and 20ma is more
than enough.? But then even 10ma is enough current for 5mW.
Allison
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Re: 2N2222A vs 2N3904 sourcing
I could be wrong about the device, but read someone well known referred to the 2n2222 as the cockroach that would not die as it seems like that one has been around for 50 or more years.
de ku4pt
On Thu, Sep 13, 2018 at 5:15 PM Jerry Gaffke via Groups.Io <jgaffke= [email protected]> wrote: Kees,
Otherwise unobtainable plastic 2n2222A's available for pennies on ebay?
In this particular case, I'm not so sure about the first part in "Trust, but verify".?
But certainly possible, the recipe has been out there for 50 years.
Ebay might be worth a shot if you want a bunch.
For small quantities on prototypes, I'd just give Mouser their $2 for item?610-2N2222A
If you really want a bunch, then Mouser item?583-2N2222A from Rectron is $0.21 each at quantity 10000.
All 2n2222A's on Mouser have metal cans, which should dissipate more than anything plastic.
Especially if you put some sort of heatsink on them.
Or give them a liquid nitrogen bath.
There are parts that are better than the 2n2222A's, especially if interested in operating above 20m.
Search for 2n5109 in this forum for discussion of that and other parts.
Maybe also search for BS170 too, Mouser price of $0.44 for one, $0.12 each for 100.?
_._,_._,_
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Re: 2N2222A vs 2N3904 sourcing
Thank you Kees Is it safe to assume that the emitter resistors for Q911 and Q912 are to be changed to 11 ohms as was done with the driver pairs? ? Ripley KD8UYQ ? Sent from for Windows 10 ?
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From: Kees TSent: Thursday, September 13, 2018 7:08 PM To: [email protected]Subject: Re: [BITX20] 2N2222A vs 2N3904 sourcing ? Hello Ripley,
Q92/Q93, Q96/Q97, Q911/Q912
73 Kees K5BCQ
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Re: 2N2222A vs 2N3904 sourcing
On Thu, Sep 13, 2018 at 06:24 PM, Jim Tibbits wrote:
nearly flat across the passband (10 meters is about 5-6 db down)
Jim,
Is it flat or does it fade by 5-6db at the 10m end?? ?Seems a contradiction.
BTW what output power are you getting.? For the drivers it needs to be a half watt (27dbm).
for the predrivers it will be the stage gain less but likely 50 or more mW (17dbm).
Even q90 has to be good to maybe 3-5mW (about 7dbm).? ?I say this as small
signal performance is not always a predictor of high power behavior.? And
since the amp has a serious IMD problems over 2W some stages are
collectively?are?running short.
The amps pass band for the amp is 3.5mhz to 29.99 Its anything but flat.
As there are many (all) that are not flat as in well over 12W at 80m and maybe 2W
at 10m.? IF it were flat to 3db it would be 6W at 10M not 2w.
This is what I've been saying for months.? The only way to get flat from 3-10mhz with 3904s
is dial the stage gain down to maybe 11DB.? The only problem with with all four stages
weighing in at under 43-45 DB total your well below what is required to? get 10W out
from the last mixer to the antenna.? FYI the mixer output at -17dbm is dirty so its not
a good idea to push for more.? Last I checked from -17 to +40dbm is a mere 57db of gain.
You might get 10W if each stage averages 14.4db across the full band width.
Your SA proves that is not going to happen.? Getting 11db and flat is possible
but you run out of gain and there is no physical place to add a stage.
The part does not have the FT and the Gain/bandwidth product to do that.
It also has a gain(hfe) that decreases with collector current.? At full power the
collector current is NOT 20ma. ( I'd expect about 42 to 45ma per transistor).
The exception for that would be q90 as its true class A and 20ma is more
than enough.? But then even 10ma is enough current for 5mW.
Allison
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Re: 2N2222A vs 2N3904 sourcing
You guys are just getting silly now ...Pushing 3904's indeed ,,,Just breadboarded the DC circuit in the PA (22 ohm emitter resistor, 100 ohm base bias and 1k collector ..Guess what? 20.1 ma ...EMRFD fig 6.140 Q102 has emitter resistor 100 ohm. base bias 680 ohm and collector 2.2k?? 20 ma bias also, too....
Just a picture of the "tentative" PA amp chain ...nearly flat across the passband (10 meters is about 5-6 db down ..Still playing with replacements for T10,T11 and maybe T9 Jim
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ka9koj here,
jeff i ordered a 45 mhz filter too to take care of the spurs. as for the harmonics , i plan to leave the filters alone on the board and build an external filter box manually switched. kind of like the old days when you screwed in an inline filter between transmitter and antenna.im planning to try to build them for each band switchable and a toggle to bypass for general shortwave reception. dont know if its a good idea but i really dont want to tear apart my rig. when they come out with a ver 5 maybe they will have the 45mhz filter installed and other changes.i have ver3.i need to buy another one that isnt wired up,cabineted,and sealed.
if i read right, wa8tod stated the 45mhz filter takes care of all spurs.that is a good thing.harmonics are another thing.some stages might be overdriven, causing some harmonics, broad values for the filter sections can cause it ,not rejecting other frequencies, weird oscillations,feedback,etc. but with the coils re wound,or stripped out and mounted on a separate board will probably do the trick. ham radio is sooooo exciting!!!!!!!
David
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Re: 2N2222A vs 2N3904 sourcing
Kees,
Yes they are being pushed and for the 5th time in this conference its more than that
the 3904 does not maintain its gain with increased current unlike the 2n2222A.? ?
Dig back its here.
Another property is some trasustors exhibit higher gain/bandwidth with increasing
current and some don't.? So comparing them on FT is not as simple as it first appears.
The 2n2219 is the same part as 2222 (internal silicon) in a to5/to39 for better heat transfer
and is higher power.? ?The only difference in those cases is one has a glass filled base
and the other is metal with glass leads seals.
Allison
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Re: 2N2222A vs 2N3904 sourcing
All take care on this transistor in terms of what case size you get it in.. it was manufactured in two sizes T0-39 and the smaller TO-18 metal case size.? It appears from the Newark description? that the larger case size is being offered in this case.? The Toroid king in FL has them the TO-18 size at a good price too (and probably at much lower shipping cost ).? Heat sinking - your mileage may vary.? The? 2n3053 part that Newark also list as a semi equivalent is also a good part up to at least 20Mhz but may get a little sad after that.? It has been used in plenty of 7 Mhz and 10 Mhz kits in the past.? (NB it is nominally about 50 percent better on HFE than the first part).? The? 2n2222A or 2219 is the better? choice for the predriver as they have lower common emitter capacitance which will be a major driver in that position. Obviously if you put in a more capable device you can drop the emitter resistors? (even by putting? a TH resistor on an emitter leg direct to GND for startup experiments ) , within limits as they are preventing thermal runaway .... and ....it is all fun.
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Re: 2N2222A vs 2N3904 sourcing
For those who worry
about the 2N3904.
This is a big brother
that was used a long time ago, a step up from the 2N2222A,
just bigger.
Mouser has them, but at more $ ?
Mike, WA6ISP
On 9/13/2018 4:28 PM, Kees T wrote:
Nick,
The Spec Ft is the same for both 2N2222A and 2N3904 .....300 MHz,
but the Ic max for the 2N2222A is more than twice that of the
2N3904. Someone (Allison ?) had mentioned the 2N3904s were really
being "pushed". That's why they are paired.
73 Kees K5BCQ
--
Mike Hagen, WA6ISP
10917 Bryant Street
Yucaipa, Ca. 92399
(909) 918-0058
PayPal ID "MotDog@..."
Mike@...
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Re: 2N2222A vs 2N3904 sourcing
Nick,
The Spec Ft is the same for both 2N2222A and 2N3904 .....300 MHz, but the Ic max for the 2N2222A is more than twice that of the 2N3904. Someone (Allison ?) had mentioned the 2N3904s were really being "pushed". That's why they are paired.
73 Kees K5BCQ
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Re: 2N2222A vs 2N3904 sourcing
Hello Ripley,
Q92/Q93, Q96/Q97, Q911/Q912
73 Kees K5BCQ
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Re: K5BCQ uBITX Relay Switched LPF/BPF board
Hello Art,
A complete 6x kit includes: a 6x board, 12 relays, 6 blank LPF boards, headers, diodes, capacitors and a 6 position rotary switch for $30 plus $4 for postage in the USA.
73 Kees K5BCQ?
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WS1M - bammi
Ripley
