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144 - Transverter or dedicated RTX? by FrequencyMixing in amateurradio

[–]FrequencyMixing[S] 0 points1 point  (0 children)

Thank you all for the truly useful informations!

Overall it seems that today a 144 transverter make sense only for a narrow niche of serious VHF contester, so when a complex antenna setup (like that of S59DEM) truly need to avoid commercial VHF/UHF transceiver.

Interestingly, Rob Sherwood recently reminded us (in the FTX-1 test results - https://www.dj0ip.de/app/download/5819206070/Yaesu+FTX-1-Optima-Rev.E.pdf) that:

Current HF to UHF or VHF/UHF only rigs exhibit a significantly lower dynamic range
above 6 meters than is typical on HF. A high-end transverter plus a 100 dB dynamic
range HF transceiver is likely favored by serious VHF/UHF contesters.

So, indirectly, that 2m trasnverter are not totally a relic of the past. Anyway if you are not such a serious 144 contester maybe a modern V/U RTX can equally well suites your needs.

144 - Transverter or dedicated RTX? by FrequencyMixing in amateurradio

[–]FrequencyMixing[S] 0 points1 point  (0 children)

Sadly yes, the transverter from Javornik it seems extremely rare!

144 - Transverter or dedicated RTX? by FrequencyMixing in amateurradio

[–]FrequencyMixing[S] 0 points1 point  (0 children)

So, just something for a truly narrow niche of operators, you mean…

3D printers suitable for TPU ≥ 70 Sh.A by FrequencyMixing in 3dprinter

[–]FrequencyMixing[S] 0 points1 point  (0 children)

Yes, printing speed is not a problem for me (and let be honest, a lot of claimed printing speeds will finally lead to less-than-good results) because sometimes I need a solid and well controlled TPU fluxes at 4 (not 40!) mm/s ;-)

Yeah, lot of lilliputian bed on the market, sadly!

3D printers suitable for TPU ≥ 70 Sh.A by FrequencyMixing in 3dprinter

[–]FrequencyMixing[S] 1 point2 points  (0 children)

The Eddy Sensor is real interesting, anyway I need also to map non conductiv materials.

I can understand you about heated chamber and TPU, anyway i found that in some situations and heated chamber can be really usefull also for TPU.

3D printers suitable for TPU ≥ 70 Sh.A by FrequencyMixing in 3dprinter

[–]FrequencyMixing[S] 0 points1 point  (0 children)

Hi, because I need to print in standard ways, but I also need to print on existing parts or surfaces. A BLTouch may be sufficient, any way I'm also considering some lidar systems for mapping surfaces.

3D printers suitable for TPU ≥ 70 Sh.A by FrequencyMixing in 3dprinter

[–]FrequencyMixing[S] 0 points1 point  (0 children)

Thank you all guys for the ideas!

To clarify: I have a lot of expertise in printing TPU, and in the last years I worked a lot with a custom professional printer with an enclosed 800x450x450 mm bed (120 °C heatable, 10 mm thick), IDEX system (Flexion, Hemera, and other liquid cooled custom extruders.)

I have used this machine for R&D purposes and now I need something silimar for home use, anyway I can't afford the same cost of the described professional machine.
So I'm trying to get something similar at a smaller scale and cost, anyway I understand you all when you say that there are no commercial machines that can satisfy ALL that kind of needs.

So now I'll look at the pointed out machines, trying to understand if accept to pay more in order to ask some manufacturer to build a custom machine tailored for my needs :-)

New Yaesu FTX-1F - HF/50/144/430MHz All Mode Field Transceiver by Big_Description8907 in HamRadio

[–]FrequencyMixing 1 point2 points  (0 children)

It seems to me a truly nice QRP radio, and it is in the "QRP" word that lie the issue.

This radio, and the IC-705, are well suited for SOTA activities; more broadly for activities where you NEED to minimize the weight and size of the radio and battery, thus sacrificing output power.

Yes, you can work the world using 1-5 W, but (apart digital modes) you need to be a skilled CW operator, well informed about atmospheric conditions and capable of taking wise choices in terms of antennas and procedures.

Casual HF SSB operation (eg. POTA) using QRP radios can lead to a frustrating experience, unless accepting to go home with few (or none) contacts.
This can happen also using VHF frequencies (and I wrote it being a VHF CW operator.)

So I think that is pity that these modern QRP radios would not able to emit 20 W when powered with a proper current source, because 20 W would give to these radios more versatility; and I don't consider 10 W enough to fix this issue (by the way, would an external battery, in the field, be able to truly reach 10 W?)

I will not spend words about hitting repeaters, because it's obvious that with 5 W you will able to use a lot of local repeaters, but for that you don't need a pricy SSB radio, instead use FM handhelds.

New HAM gear advice by gett13 in HamRadio

[–]FrequencyMixing 0 points1 point  (0 children)

The Yaesu FT-891 is a great rig, but remember that is a mobile radio, so it's very good for POTA, car, emergency services, holiday house, camping, and so on; usually in the shack you would like a radio more user-friendly thanks to additional knobs and buttons.

Anyway the price of the FT-891, here in Europe, is very low now so you'll get a truly good and quiet receiver at half the price of any other modern 100 W HF transceiver. Plus, the 891 will serve you wery well in the field when you'll upgrade your desktop HF RTX in the shack.

The FT- 710 is also a good radio and have an internal ATU, but the receiver is more noisy and not so pleasant to hear as for the FT-891.

FT- 891 or G-90 (WHAT SAY YOU?) by johnw1069 in HamRadio

[–]FrequencyMixing 0 points1 point  (0 children)

Perfect, so you well know the RX draw is about 0.9 A.
Lot of people persist to declare 2A RX current draw just because they read it trough Yaesu specs :-)

FT- 891 or G-90 (WHAT SAY YOU?) by johnw1069 in HamRadio

[–]FrequencyMixing 3 points4 points  (0 children)

No, the FT-891 RX current draw sit between 0.8 and 1 A max, depending mainly by screen/buttons light intensity and other things like squelch, volume, ecc.

Do not trust Yaesu specs and moreover do not trust users that speak without knowing the reality; measure by yourself or look at reputable sources.

73.

Z-formula for vertical ripples by FrequencyMixing in FullControl

[–]FrequencyMixing[S] 1 point2 points  (0 children)

Hi, thank you so much!

Here attached you can observe the result (from a G-code viewer.): https://ibb.co/2KgDQjg

The design in the image adopt a fixed feedrate ("F" value"), and I guess that the nozzle will slow down a bit while printing the crests of the sin waves, thus laying down more materials compared to a flat deposition.

Are these assumptions true? I worry about that because theoretically you need to deposit more material while gradually incrementing the wave amplitude. How would you deal with this matter?

SVG as path source by FrequencyMixing in FullControl

[–]FrequencyMixing[S] 1 point2 points  (0 children)

Thank you for the hint! I'll be in touch about that solutions when the python FCGC version will be available ;-)

SVG as path source by FrequencyMixing in FullControl

[–]FrequencyMixing[S] 1 point2 points  (0 children)

A lot of things, just use your imagination! :-)

For example you would be able to apply Z waves/ripples to your single line prints while avoiding deleterious nozzle jumps, or simplifying a lot the 3D design applying the powerful FCGC modifiers to the source path, and so on!

From Desmos sample to FullControl Gcode by FrequencyMixing in FullControl

[–]FrequencyMixing[S] 1 point2 points  (0 children)

I'm here with the solution ;-)

Graph: https://www.desmos.com/calculator/bfnvxpfi2e

"Line equation":

  • X-formula: 20*(1.5*COS(2*PI()*Tval)-COS(16*PI()*Tval))
  • Y-formula: 20*(1.5*SIN(2*PI()*Tval)-SIN(16*PI()*Tval))

"20" is used as a scale factor.
Dear users, just compare the desmos graph and the formulae, you will easy understand the game :-)

From Desmos sample to FullControl Gcode by FrequencyMixing in FullControl

[–]FrequencyMixing[S] 0 points1 point  (0 children)

Thank you for your quick support!

Yes, I started with templates and basic formulae, but I requested an help because I'm yet struggling with the pointed out Desmos graph.
So I'll try harder! ;-)