Re: Harmonic performance - SSB vs CW
On Sat, Aug 4, 2018 at 07:07 PM, Jerry Gaffke wrote:
Looks to me like a good part of the problem is board layout.
Each LPF is fed from a relay, then has a trace from the far side of the LPF
coming back right under the LPF to get back into the other set of relay.contacts.
One possible solution:
Rip out that return trace on each of the LPF's.
Add a set of straps at the far end of the LPF's to select one of them for connection to the antenna jack.
Jerry, I split that. Part of the problem is internal to the relay isolation from one set of contacts to the other. You cannot parallel those filters. They must be switched.? Also currents flowing along the ground plane are mixed in.? Several things going on not just one.? No simple answer. Allison
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Re: Harmonic performance - SSB vs CW
Jerry,
Warren has a little data an SSB.? ?It also varies with any amp mods and how hard you push
power either by RV2 or mic gain.
Right now I think SSB is better than CW for harmonics but its been a long time
since mine was stock.? ?One thing for sure even with the most linear amp GIGO
and that I've seen using a external instrumentation amp.
There is no question the amount of filtering is marginal.
Allison
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Re: Raduino Clone kit from W0EB-N5IB
#ubitx
Jim, now i know what i was thinking, the 5v I2C levels from the NANO into the Si5351.
The max input to the Si5351 on I2C pins is 3.6v. (Table 8 of data sheet)
Hence i put in a logic level translator.
glenn
On Sun, Aug 5, 2018 at 12:34 PM, Glenn wrote:
Hi Jim, you are correct, not sure how I thought that......didn't look closely enough i guess.
OK on the extra bypassing etc.
glenn
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Re: Harmonic performance - SSB vs CW
NJM2073 part , if you try buying from ebay etc, you might landin getting same junky TDA2822? re-branded. Try to by from some reliable source.
On Sun, Aug 5, 2018 at 7:57 AM, Jerry Gaffke via Groups.Io <jgaffke@...> wrote: Indeed.
Maybe do a search for TDA2822 on the forum to review the discussion
before launching into an angry rant.??
Here's a brief summary:
All uBitx's from HFSignals get powered up and checked and calibrated at 12v before shipping.
ST hasn't been building TDA2822's in the DIP8 for years.
HFSignals was buying FCI branded TDA2822's, they worked fine.
Their supplier switched to WX branded parts when the FCI parts were not available.
Boards with the WX parts worked fine at HFSignals during final board test.
The WX parts mostly work, typically power up fine.
But can blow on a whim if powered from 10v or more.
Perhaps a faster rise time on the supply or a supply set to 13v would blow a WX part
Perhaps a brief short at the headphone jack.
Perhaps no reason at all.
The NJM2073D from JRC is a good solid pin compatible replacement for the TDA2822,?
Easy to get.
?
Better yet, don't launch into an angry rant.
I don't do angry, and I for one will definitely be ignoring the next one.
Except perhaps to ask the moderator to take action.
Jerry, KE7ER
?
On Sat, Aug 4, 2018 at 06:31 PM, ajparent1/KB1GMX wrote:
Seriously!? Take a moment and a deep breath.
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Re: Raduino Clone kit from W0EB-N5IB
#ubitx
Hi Jim, you are correct, not sure how I thought that......didn't look closely enough i guess.
OK on the extra bypassing etc.
glenn
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Re: Harmonic performance - SSB vs CW
Indeed.
Maybe do a search for TDA2822 on the forum to review the discussion
before launching into an angry rant.??
Here's a brief summary:
All uBitx's from HFSignals get powered up and checked and calibrated at 12v before shipping.
ST hasn't been building TDA2822's in the DIP8 for years.
HFSignals was buying FCI branded TDA2822's, they worked fine.
Their supplier switched to WX branded parts when the FCI parts were not available.
Boards with the WX parts worked fine at HFSignals during final board test.
The WX parts mostly work, typically power up fine.
But can blow on a whim if powered from 10v or more.
Perhaps a faster rise time on the supply or a supply set to 13v would blow a WX part
Perhaps a brief short at the headphone jack.
Perhaps no reason at all.
The NJM2073D from JRC is a good solid pin compatible replacement for the TDA2822,?
Easy to get.
?
Better yet, don't launch into an angry rant.
I don't do angry, and I for one will definitely be ignoring the next one.
Except perhaps to ask the moderator to take action.
Jerry, KE7ER
?
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On Sat, Aug 4, 2018 at 06:31 PM, ajparent1/KB1GMX wrote:
Seriously!? Take a moment and a deep breath.
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Re: Raduino Clone kit from W0EB-N5IB
#ubitx
Glenn, The Si5351 never ran on 5 volts even on the original Raduino. ?It takes its voltage from the 3.3V regulator built into the NANO via the 3V3 pin on the header. ?No need to supply extra parts for the 3.3V but I did add additional filter capacitance on the 3.3 to the 5351 so suppress some of the RFI clicks that had been reported. ?I added an additional 10uF capacitor to the 3v3 line and it seems to have really helped kill the tuning clicks feed back into the supply from that line.
The 7805 5V regulator is also heavily bypassed unlike the original and has both .1uf ceramic and 10uF Tantalum capacitors on both the input and output of the 7805 in accordance with standard industry practice. ?Except for the 2 tantalum capacitors on the 7805 and the 10uF on the 3.3V line, all the capacitors are 0805 size SMD capacitors. ?Resistors except for R1 and the two trim pots are 0805 size SMD 1/8W 5%.
The full construction manual containing the parts list, schematic and board trace pattern is downloadable from the Documentation directory in the "files" section on my website,
Jim Sheldon, W0EB
------ Original Message ------
Sent: 8/4/2018 7:26:16 PM
Subject: Re: [BITX20] Raduino Clone kit from W0EB-N5IB #ubitx
Jim, did you fit parts to run the Si5351 from 3v3 and not 5v of the original Raduino?
I have made a similar board to your Clone also, with these parts fitted although same size as original. The Si5351 is a DIY also here, but can? use the Adafruit version too. I also made provision for a TXCO reference, a FOX924.
vk3pe
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Re: Harmonic performance - SSB vs CW
Looks to me like a good part of the problem is board layout.
Each LPF is fed from a relay, then has a trace from the far side of the LPF
coming back right under the LPF to get back into the other set of relay.contacts.
One possible solution:
Rip out that return trace on each of the LPF's.
Add a set of straps at the far end of the LPF's to select one of them for connection to the antenna jack.
I haven't been following closely, has anyone reported any numbers on just how bad
these harmonics are during SSB ops?? ?
Jerry
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On Sat, Aug 4, 2018 at 06:28 PM, ajparent1/KB1GMX wrote:
Using two of the current ones would yield a very good result as on would be literally physically
on the other side of the filter for a good layout.
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Re: Harmonic performance - SSB vs CW
Houston, we have had a problem !!!;-)
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Re: Harmonic performance - SSB vs CW
Tim,
Seriously!? Take a moment and a deep breath.
Allison
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Re: Harmonic performance - SSB vs CW
Gordon,
There are relays that can offer better isolation but the cost is higher (omron G3 series is good
and the G6 series works well to 3ghz) but you pay for that.? using 4 of either would?
cost more than the uBitx.
The pictured relay is not an option though with internal mods I've made them work
for TR service at 6M.? But its something that takes time and is very not production
friendly.
Using two of the current ones would yield a very good result as on would be literally physically
on the other side of the filter for a good layout.? But you still need twice as many (6 vs 3).
But they can be had at very low cost.
Allison
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Re: None supprest carrier in TX
Hi, I think all ok with BFO for example LSB = 11996350 as I reconstructed filter to real 8 crystals. Filter shape hase become near 2 and not 3.5 as it was. But carrier as it was on the same place - I have side band and full carrier!
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Children, play nice please. -- Lee - N9LO? "I Void Warranties"
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Re: Harmonic performance - SSB vs CW
Looking closer at what you folks (Warren the first to report...) have discovered
E.g.: ?¡°In my testing I also found the isolation across one relay was barely 45db in one configuration and 50 in another.Using one relay to switch both ends of a filter will compromise the filter ¡°
It may be worth it to now look at the physical construction of the relays first. ? Perhaps there is a way to insert a shield between sets of contacts. I have it disassembled any of mine yet and couldn¡¯t find an image but
the construction might be similar to this:?
On Aug 4, 2018, at 20:07, ajparent1/KB1GMX < kb1gmx@...> wrote:
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Tim, no on the Diz amp.
First mine is linear (class AB1 150ma per irf510), the base amp was class C.?
About all I did?use was a few passives and the board itself. Used a differnt wind for
all the coils going from bipolar to mosfet? FYI the results were at 13.6V.? ?At 20V
it does a nice 16W and the 10M power is 10W.? Power supply runs out at 20V
and I didn't need that much anyway but had to turn it up and see.? ?Due to the
really good RF layout of the board it has proved to be stable and blast proof.
Years of design and build I have a lot of unobtainium and some exotica.
And a junk box with stuff that dates back to the 60s.? I lived in Grumman
LM country.
Allison
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Awww. I'm heartbroken.
Vince - K8ZW.
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On 08/04/2018 08:26 PM, Timothy Fidler wrote: Me foolish .
The facts the STD TDA 7622 can take 13.8 / 14 V .. above 15V there is a
problem. This guy hopefully started up his PCB on near 12V. The TDA
blew. it was likely as shtty Chino knock off of the proper ST design. I
knew about the issue (you will find and earlier post from me on matter
if YOU LOOKED ??) but it still raises the question.. Did the Factory
power up the board and functionally check it or not ? It is highly
suspect that even if they powered it up at 14V ie within voltage spec
the part would have blown. As for your rather snotty reply even though
you provided data quickly on the pre driver .. if you want info on the
14 W output CL-A mod set you can go to hell. I will provide that only
to the OP if he emails it to me or anyone else but not you. TEF
--
Michigan VHF Corp.
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Heavens folks can¡¯t we be a little bit more civil?
On Aug 4, 2018, at 20:26, Timothy Fidler < engstr@...> wrote:
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Me foolish .?
The facts the STD TDA 7622 can take 13.8 / 14 V .. above 15V there is a problem.? This guy hopefully started up his PCB on near 12V. The TDA blew.? it was likely as shtty Chino knock off of the proper ST design. I knew about the issue (you will find and earlier
post from me on matter if YOU LOOKED ??) but it still raises the question.. Did the Factory power up the board and functionally check it or not ? It is highly suspect that even if they powered it up at 14V ie within voltage spec the part would have blown.
As for your rather snotty reply even though you provided data quickly on the pre driver .. if you want info on the 14 W output? CL-A? mod set you can go to hell.? I will provide that only to the OP if he emails it to me or anyone else but not you. TEF
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Me foolish .?
The facts the STD TDA 7622 can take 13.8 / 14 V .. above 15V there is a problem.? This guy hopefully started up his PCB on near 12V. The TDA blew.? it was likely as shtty Chino knock off of the proper ST design. I knew about the issue (you will find and earlier post from me on matter if YOU LOOKED ??) but it still raises the question.. Did the Factory power up the board and functionally check it or not ? It is highly suspect that even if they powered it up at 14V ie within voltage spec the part would have blown. As for your rather snotty reply even though you provided data quickly on the pre driver .. if you want info on the 14 W output? CL-A? mod set you can go to hell.? I will provide that only to the OP if he emails it to me or anyone else but not you. TEF
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Re: Raduino Clone kit from W0EB-N5IB
#ubitx
Jim, did you fit parts to run the Si5351 from 3v3 and not 5v of the original Raduino? I have made a similar board to your Clone also, with these parts fitted although same size as original. The Si5351 is a DIY also here, but can? use the Adafruit version too. I also made provision for a TXCO reference, a FOX924. vk3pe 
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A serious answer is that at 36V the IRF510 has no SWR latitude the slightest
bump or bad SWR and they disappear.? Stay? in the 24-28V is far more reliable
assuming its RF stable and doesn't oscillate which is not a safe bet from what
I've heard.
With 2W drive a pair of IRF510s in a good design should hit about 50-60W at 28V.
That's what the WA2EBY amp can do.? You need the board layout to support that.
The driver should be improved but at 7mhz the 2n2219 is a good part.
Watch for parts that can't stand the DC voltage.
Generally doing that with the BITX40 is not going to fly long as the
low pass filter parts are not up to it.
Allison
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PN? is 2n3866 1.5 W RF NPN silicon but based on recent reply it seems the smaller metal cased part was used as the pre driver on many boards.
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Jim Sheldon
George
Lee