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Hello ? Do you have any recent experience of buying a generator of this type. Please send me references of such a product. ? Thank you -- F1AMM Fran?ois
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Bonjour Francois,
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The last two-tone generator I purchased was
a kit from Elecraft.
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Hal Mandel
W4HBM
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Thank you ? Here is one:
? Arg $140 as they humorously write: Order a couple, build both and give away one as a gift! Spread the word: Elecraft kits and accessories are now in stock at DX Engineering! De la part de Tim Duffy K3LR
贰苍惫辞测é?: vendredi 17 janvier 2025 17:13
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Francois,
There are a number of 2-tone software apps that could drive a
computer sound card with very high quality output.? If you have a
computer (or laptop) near the workbench or shack, maybe that's an
easy solution.
73/jeff/ac0c
alpha-charlie-zero-charlie
On 1/17/2025 10:06 AM, Fran?ois via
groups.io wrote:
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Hello
?
Do
you have any recent experience of buying a generator of this
type. Please send me references of such a product.
?
Thank
you
--
F1AMM
Fran?ois
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U can test a xcvr? with a 2 tone....? but not a linear amplifier (the exception being if using a xcvr with Class A, like the yaesu, and even that won't work in my case, since the MK-V only puts out 75 watts in Class A, which is not enough? to drive the L4B? nor the hb 3x3).?
?
To test an amp with 2 x tones requires? 2 x separate xcvr's, each on CW cxr mode..... driving a? combiner that in turn drives the linear amp.? ?Then u can use any freq spacing you want.?
If a 2 tone? audio signal is fed to the class AB? ?XCVR....that then drives a linear amp, the IMD? from the xcvr will be a magnitude worse than the typ tube amp.?
On one of my DENON test cd's.... one of the tracks is a 2 tone, for doing IMD tests, but the 2 x tones they use? are not compatible with? typ ham gear.? (spacing too great, and out of the typ BW of a ssb xcvr).
Like Jeff sez,? just use a? 2 tone app, that drives the sound card in a PC.?
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I would like to understand your participation but I am already very constrained by the use of abbreviations and certain words that Google does not translate for me. ? ·???????? xcvr xcvr's ·???????? MK-V ·???????? L4B ?nor the hb 3x3 ·???????? DENON test cd's Sorry -- F1AMM Fran?ois De la part de Jim VE7RF via groups.io
贰苍惫辞测é?: dimanche 19 janvier 2025 06:58
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Francois, I've been experimenting with a RFZero board. RFZero is an Arduino based signal generator with many, many different applications. The RFZero team has written Arduino scripts available for free download to operate the RFZero, including a two-tone generator function. The RFZero has an integrated GPS receiver so the output signal is GPS disciplined; all you have to add is an external GPS antenna & they are readily available inexpensively. The RFZero board costs ~$70 U.S. It is the basis for a project,?not?a finished product but if you enjoy building you?can make it be what you want yourself rather inexpensively.? I'm planning to use the RFZero boards as the basis for a set of propagation beacons on 10m - 70cm.? Bo, OZ2M is very supportive of the RFZero product.?
Thanks,
Robin Midgett K4IDC
Hello ? Do you have any recent experience of buying a generator of this type. Please send me references of such a product. ? Thank you -- F1AMM Fran?ois
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Dimanche, 19 Janvier, 2025; 1148 EST
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Dear Francois,
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XCVR = Transceiver, a Transmitter and Receiver in the same box.
??????????????? Often referred to as “Tx or TX,” and? “ Rx or RX” thus: “TRX.”
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MK-V =? The Yaesu FT-1000 Mark-5 transceiver
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L4B = The Drake Model L4B linear Amplifier
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“3X3” = The Eimac (or equivalent) 3 cx 3,000 ceramic tube (valve).
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“Denon test cd’s”??? Now there you have me, Francois. I don’t know.
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Bon Chance! et ’73,
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Hal Mandel
W4HBM
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XCVR is an abbreviation for Transceiver
MK-V is a Yaseu Transceiver
L4B is a model of an old Drake amplifier
DENON test
cds are Compact Disks for DENON test equipment
Abbreviations and model nomenclature are always going to be difficult for translation programs to figure out.
?
XCVR est une abréviation de Transceiver
MK-V est un Transceiver Yaseu
L4B est un modèle d'un ancien amplificateur Drake
Les CD de test DENON sont des disques compacts pour les équipements de test DENON
Les abréviations et la nomenclature des modèles seront toujours difficiles à comprendre pour les programmes
de traduction.
?
73,
Dave, w6de
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From: [email protected]
<[email protected]> On Behalf Of Fran?ois via groups.io
Sent: 19 January, 2025 06:12
To: [email protected]
Subject: Re: [ham-amplifiers] Two tones test generator
?
I would like to understand your participation but I am already very constrained by the use of abbreviations and certain words that Google does not translate
for me.
?
-
xcvr xcvr's
-
MK-V
-
L4B ?nor the hb 3x3
-
DENON test cd's
Sorry
--
F1AMM
Fran?ois
De la part de
Jim VE7RF via groups.io
贰苍惫辞测é?: dimanche 19 janvier 2025 06:58
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Be careful when conducting 2 x tone tests.? You can easily manipulate / skew? the results by? manipulating the tone spacing.? ?Manufacturer's would do just that, years ago, to minimize IMD3 and IMD5....meanwhile higher order IMD was degraded.? That, and also manipulating the bias? to improve results.? Typ only IMD3 and IMD5 results were stated.?
My other issue with the 2 x tone test? is everything is in a steady state.? ?IE:? B+ / bias / screen voltage / fil V etc, etc...don't budge.? ?They are static, not dynamic.? ?Then toss in lousy ALC setups on some xcvr's.....which will further degrade IMD when ssb used.? The 25 ohms of DC resistance on each? grid choke in a SB-220? will result in a 3.75 V drop across each choke. (25 ohms dcr x 150 ma grid current per tube).? ?Ok, now the bias yo-yo's up/down? from 5 vdc (zener Vdc) to 8.75vdc, when driven.? That plus the instantaneous B+ will sag with full bore plate current peaks on ssb.? ?That mess will screw up the load line.?
IMO, you may be better off? with? just talking on SSB, and looking at the output on a SA (spectrum analyzer).? It's the higher order IMD products, like IMD 7-9-11-13-15-17-19? ?that cause the splatter.?
I got into it with JI, years ago,? about the tone spacing.? For his argument against ESSB he would use extreme wide tone spacings,? like 100 hz and 3200 hz on a MK-V? ( in DSP TX mode).......... or 50 hz and 5700 hz? on a modified MK-V.....(in analog mode with a pair of 6 khz filters installed).?
Try as hard as you can, but with normal speech, you can't achieve SIMULTANEOUS? lows and highs.? ? It's one or the other, but not both at the same time.? ?I tried every trick in the book, and no words, phrases will result in simultaneous highs + lows.? The only way to achieve simultaneous highs + lows is...... (A)? JI's convoluted 2 x tone tests, with extreme wide spacing.... or (B)? program material,? eg: rock and roll music fed into the xcvr.?
The 2 x audio tones fed into the xcvr will only test the xcvr.? ?With the linear amp in the circuit, the resulting IMD is no better than the xcvr.? The K3 is rated at -29db pep? (-23 dbc)? for IMD3...at 100 w pep out.? How the hell are you gonna test your L4B / SB-220? etc? ???? ?You can't.?
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Another way to check for linearity is to use pink noise as an input: all frequencies in the pass band simultaneously. A perfectly linear system would reproduce exactly the input spectrum as the output. The difference can be used to define the lack of linearity and its nature.?
Kim N5OP
"People that make music together cannot be enemies, at least as long as the music lasts."?-- Paul Hindemith
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On Jan 20, 2025, at 4:55?AM, Jim VE7RF via groups.io <jim.thom@...> wrote:
? Be careful when conducting 2 x tone tests.? You can easily manipulate / skew? the results by? manipulating the tone spacing.? ?Manufacturer's would do just that, years ago, to minimize IMD3 and IMD5....meanwhile higher order IMD was degraded.? That, and also manipulating the bias? to improve results.? Typ only IMD3 and IMD5 results were stated.?
My other issue with the 2 x tone test? is everything is in a steady state.? ?IE:? B+ / bias / screen voltage / fil V etc, etc...don't budge.? ?They are static, not dynamic.? ?Then toss in lousy ALC setups on some xcvr's.....which will further degrade IMD when ssb used.? The 25 ohms of DC resistance on each? grid choke in a SB-220? will result in a 3.75 V drop across each choke. (25 ohms dcr x 150 ma grid current per tube).? ?Ok, now the bias yo-yo's up/down? from 5 vdc (zener Vdc) to 8.75vdc, when driven.? That plus the instantaneous B+ will sag with full bore plate current peaks on ssb.? ?That mess will screw up the load line.?
IMO, you may be better off? with? just talking on SSB, and looking at the output on a SA (spectrum analyzer).? It's the higher order IMD products, like IMD 7-9-11-13-15-17-19? ?that cause the splatter.?
I got into it with JI, years ago,? about the tone spacing.? For his argument against ESSB he would use extreme wide tone spacings,? like 100 hz and 3200 hz on a MK-V? ( in DSP TX mode).......... or 50 hz and 5700 hz? on a modified MK-V.....(in analog mode with a pair of 6 khz filters installed).?
Try as hard as you can, but with normal speech, you can't achieve SIMULTANEOUS? lows and highs.? ? It's one or the other, but not both at the same time.? ?I tried every trick in the book, and no words, phrases will result in simultaneous highs + lows.? The only way to achieve simultaneous highs + lows is...... (A)? JI's convoluted 2 x tone tests, with extreme wide spacing.... or (B)? program material,? eg: rock and roll music fed into the xcvr.?
The 2 x audio tones fed into the xcvr will only test the xcvr.? ?With the linear amp in the circuit, the resulting IMD is no better than the xcvr.? The K3 is rated at -29db pep? (-23 dbc)? for IMD3...at 100 w pep out.? How the hell are you gonna test your L4B / SB-220? etc? ???? ?You can't.?
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On Mon, Jan 20, 2025 at 03:51 PM, Kim Elmore wrote:
>Another way to check for linearity is to use pink noise as an input: all frequencies in the pass band simultaneously. A perfectly linear system would reproduce exactly the input spectrum as the output. The difference can >be used to define the lack of linearity and its nature.?
?
>Kim N5OP
Excellent idea...... and I had forgotten all? about it.? ?My Behringer DEQ-2496? ( 24 bit - 96 khz)? mastering processor has a pink noise generator in it.? ?I checked my old notes, and when fed into the XCVR ( via a ton of rack audio gear, used for ESSB)? it's easy to achieve normal, max PEP output out of the xcvr and also the linear amp.? ? On the DC input side, the DC plate current with pink? was exactly 1/2 of a dead CXR.? ?IE:? 50% duty cycle....same as 39 wpm dots.? On a pep meter, it wavered? just a tiny bit.? ?I experimented and could easily tune up the linear with it.? ? It sounds cool over the air too.? Folks who are unaware, wonder what the hell they are listening too.? I would flip to the opposite sideband, tune up, the swap sidebands again. Pink noise has equal level per octave.? ?White noise increases? 3 db for each octave.? ?Each octave doubles in upper freq.? ?IE: 100hz - 200 - 400 - 800 - 1600 - 3200? -? 6400 hz.? ?As you go up in octaves, the BW keeps doubling.? And with double the BW, the noise doubles, hence the 3 db increase per octave with white noise.? To generate pink noise, they start with? white noise..... then run it through a 3 db per octave roll off filter...... dead simple.? ?The trick is, at what freq does the roll off start at ?? ?To do it correctly, it should be done at a very low freq, like 50 hz.? IMO,? pink noise would be better vs a 2 tone test, when conducting IMD tests.? ?The pink noise uses all the passband? freqs.? On a SA, it looks like a flat line across the passband, then drops off at both ends.? Only drawback is ( same as a 2 tone)? is everything is in a steady state.? ?But for a quick definitive IMD test,? it works superb.?
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In the same way that there are synthetic white noise generators, from a pseudo-random code, are there synthetic pink noise generators? ? This pink noise modulating in SSB seems to me to be a very good idea. -- F1AMM Fran?ois De la part de Jim VE7RF
贰苍惫辞测é?: vendredi 24 janvier 2025 19:10
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HaL Mandel
Robin Midgett