HH3 premises

[ivconic]

I was reading posts in this forum and i see plenty interesting ideas.
But what is missing are main premises for this project.
Author should give here main premises.
* What should be the main aim of HH3? High power with deep penetration (robust ps, robust TX, large coils, lower frequencies) or moderate/small power with good discrimination (tiny ps, refined TX, small coils, higher frequencies)?
* Fully digital or fully analogue...or mix between both?
* What kind of LCD; character oriented or graphical?
* What type of enclosure (on the belt or mounted on shaft)?
* Preffered battery setup (one battery or more)?
* What type of uPc (Atmel,PIC or other)?
* Coil (mono, dual...or both)?
etc...etc...
With given premises it would be easier to make suggestions...

[Carl-NC]

My preferred premise is to continue HH3 as a learning platform, not really as a cutting-edge design. But it should have very useful performance.

Anyway, here are some thoughts.

• I personally prefer PIC chips. They are plenty good enough and have outstanding support amongst experimenters. Lots of books, too. Might have to go with a 24F or dsPIC.
• Support for mono & IB loops.
• Probably go with a character display for cost & ease. HH1 & HH2 have no display, so this is a first good step. HH4 can have graphical!
• Support GB and multi-point sampling.
• Mixed analog/digital, with most processing moved to digital. HH2 has an option for direct sampling the preamp, so this is a good first step in testing ADC resolution and processing algorithms. HH3 may require a better external ADC. A decent 16-18 bit ADC with 1-2us sampling rate can be pricey and hard to obtain in some places, so I need to be careful.

- Carl

[ivconic]

I see. Eh...those are new generation PIC's. Kind a "heavy artillery" for me!
Generally i prefer PIC's more also. But last i used was 16F877/876. Old and obsolete.
But i am affraid design based on that kind of uPc will be to tough to be done in amateur workshop like mine. Most probably it would need prepared pcb and PIC already mounted on it to be offered as semi kit for those who wants to make it.
Smt or conventional? I guess smt (most logical choice). Again eh!
Problem at my country is that i can not find neither one company where real metalized double layer pcb can be done (for real metalized vias from bottom to top layer), so that presents huge obstacle to move on further. That's why we amateurs are pretty limited to do only what we can do.
128x64 LCD's are not that expensive like in the past. Actually those are cheap nowdays. Maybe to reconsider that option?
Generally you have good choice, looking promissing!
I can also suggest a more attention to be taken on audio at that design.
It is time to give up of usuall 555 buzzers (like at 90% PI's i've seen so far) and something more "colourfull" to be designed.
Such advanced uPc can be also used to generate nice and polyharmonic audio, vco behavior directly tied to the shape of processed signal (just as an example can serve audio at GP serie) .
Also i can suggest low power at TX (low drain overall) and rather to focus on good discrimination features (graphical lcd is desireable in this case). By this, design can remain compact and lightweight, also using small battery (or few) with lasting longer.
Looking promissing! Just to keep it enough "human" to be easy for us amateurs.
Looking forward..

[J_Player]

If the HH3 is to be continued as a learning platform, then we can expect there will be few options that are hard-set, in order to allow the experimenter to customize his build for his own purposes. However, I can see certain approaches are beginning to find favor, such as using a PIC control and a character display. In the overall scheme of things, it is good to have some standard hardware to form a framework for the options the experimenter may want to implement. It may be easier to crystallize the final design if some of the hardware issues are solved ahead of time. For example, if the HH3 is to use a PIC and a character display, along with a decent ADC, then maybe these components can be made available as sub-assemblies that hobbyists can order. If enough people are interested in a standard hardware package, then we may be able to see a price break that makes quality components available to the average builder. I would think the following hardware would be of interest to the average HH3 builder:

PIC mounted on PC board subassembly that permits various input/output options

Character display with any needed driver subassembly

ADC chip (several options available depending on desired speed and resolution).

Basic PCB to be used for the HH3. This could include mounting holes for the PIC and display, or could have connectors to lead to secondary PCBs that hold them, whatever makes more sense.

A complete package of other main board components such as resistors, caps, FETs etc. would be optional, as some builders would want to use different components than are shown in the basic design.

Along with these hardware items that would be useful to hobbyists, it would be also helpful if some of the talented hobbyists in this forum would produce some programming for the PIC to perform several popular adaptations of the HH3 to perform as most hobbyists would want to build it. The base programs can always be modified for special functions that some builders would want for their custom builds of the HH3.

I suppose it is premature to prepare for making hardware packages available until the design is finalized. But it may be helpful to consider the cost-saving and availability advantages of standard hardware packages when formulating the design of the HH3.

Best wishes,
J_P

[Carl-NC]

I'm sure I'll stick with thru-hole.

[Helikeon]

My preferred premise is to continue HH3 as a learning platform, not really as a cutting-edge design. But it should have very useful performance.

Anyway, here are some thoughts.

• I personally prefer PIC chips. They are plenty good enough and have outstanding support amongst experimenters. Lots of books, too. Might have to go with a 24F or dsPIC.
• Support for mono & IB loops.
• Probably go with a character display for cost & ease. HH1 & HH2 have no display, so this is a first good step. HH4 can have graphical!
• Support GB and multi-point sampling.
• Mixed analog/digital, with most processing moved to digital. HH2 has an option for direct sampling the preamp, so this is a good first step in testing ADC resolution and processing algorithms. HH3 may require a better external ADC. A decent 16-18 bit ADC with 1-2us sampling rate can be pricey and hard to obtain in some places, so I need to be careful.

- Carl

This seems to me to be an excellent starting point, Carl-NC.

Perhaps a graphical display will be more versatile for a User Menu and graphical representation of target response etc. (Graphical displays are available fairly economically now).

I suppose that the use of rotary encoders for menu navigation etc. will make the project unnecessarily complex?

Perhaps several versions with the above as possible alternatives (on satellite boards?) to a more basic model?

[Tinkerer]

Motherboard

The idea of satellite boards sounds very interesting.
It implies a motherboard.
How about a motherboard that has a versatile power supply, MCU and TX.
Satellite boards for RX, signal processing, display etc.

Tinkerer

[ivconic]

This seems to me to be an excellent starting point, Carl-NC.

Perhaps a graphical display will be more versatile for a User Menu and graphical representation of target response etc. (Graphical displays are available fairly economically now).

I suppose that the use of rotary encoders for menu navigation etc. will make the project unnecessarily complex?

Perhaps several versions with the above as possible alternatives (on satellite boards?) to a more basic model?

I agree.
Also ; no rotary encoders! God no! Few buttons will do the job just fine..

[ivconic]

The idea of satellite boards sounds very interesting.
It implies a motherboard.
How about a motherboard that has a versatile power supply, MCU and TX.
Satellite boards for RX, signal processing, display etc.

Tinkerer

Agree too. Splendid idea!

[Helikeon]

How about a motherboard that has a versatile power supply, MCU and TX.
Satellite boards for RX, signal processing, display etc. Tinkerer

Yes. This would certainly allow for a very versatile design, which will permit constructors to tinker with individual modules, without the need to completely redesign and re-manufacture the entire PCB.

Also ; no rotary encoders! God no! Few buttons will do the job just fine..

Hmmm ... rotary encoders are very reliable these days and permit rapid user-input. Granted, push-buttons are easy to implement, but in my experience, they do tend to be rather troublesome in hostile (e.g. outdoor) environments. On the other hand though, they are inexpensive, readily available and easy to replace. Careful choice is necessary.

[Carl-NC]

What's wrong with a rotary encoder?

[J_Player]

Yes. This would certainly allow for a very versatile design, which will permit constructors to tinker with individual modules, without the need to completely redesign and re-manufacture the entire PCB.



Hmmm ... rotary encoders are very reliable these days and permit rapid user-input. Granted, push-buttons are easy to implement, but in my experience, they do tend to be rather troublesome in hostile (e.g. outdoor) environments. On the other hand though, they are inexpensive, readily available and easy to replace. Careful choice is necessary.

This sounds like a versatile approach to me. If the main board contained only the power circuits and the coil circuits, then any satellite boards could be customized to control the main board as the builder sees fit. The choice of wheel or buttons could be made on a satellite board where the controls and timing components are mounted. The satellite boards could be the place where the options and modifications are made separate from the power circuits.

Best wishes,
J_P

[ivconic]

What's wrong with a rotary encoder?

I have pretty bad memory from the past related to encoders. Once i made some high resolution pll based on pic and AD9851 (if remember correctly). I couldn't find encoder at the time. So i tried somehow to dug how to replace it with diode matrix and few buttons. No success! Most of encoder types are unavailable to me here in local. I abandoned that pll project just because of that encoder, at the time.
Nowdays some of those can be find in shops, but are pretty expensive - by the rule. Mostly those are micro encoders more suitable for smt (i am talking about situation in local - not generally).
So...i would rather prefer buttons, easy to achieve; can be replaced easilly and cheap, buttons could be robust and any kind. Planning front panel on device enclosure can be easier cose there are million types of buttons.
Also...my further experiences tells me that most of encoders i saw after are easy corruptable. Usually suffers from mechanical lacks. Also most of those i saw are more than responsive to moisture..
I saw many of those are "overjumping" from time to time. Not perfect technology, especially in amateur arrangements.
But... it not suppose to be a major question at this project. Why complicate things , when ordinary buttons can be used..
Regards!

[ivconic]

BTW...if encoders were good choice - White's should be first to implement those in it's products!

I don't know if this is real and only reason; but also i am noticing certain "tendencies" at major mobile phones manufacturers in direction to elide encoders at newer products. Major - not all. I was happy user of Nokia for longer period. Than i bought Sony&Ericsson....encoder (dang!)! Than after a while it starts to overjump pretty oftenly - now i am again happy user of Nokia!!! Sony&Ericsson newer products now are having again buttons - not encoders....but it is too late! Nokia rule!

[ivconic]

Really high quality encoders are implemented at professional radios. For example i can mention Yaesu or Icom (had both). Those are pretty robust and highest quality encoders. Top of the top! But....expensiveeee!!! And not so easy to obtain..