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Bitx 40 raduino pot or encoder?

Tech Guy
 

I purchased a dds board from hf sigs for my bitx 40 just before the bitx 40 was discontinued. It came without any info. I tried it with a pot but it doesn’t tune correctly. Did they use encoders on the later dds boards like the ubitx?
John N4HNO

Don, ND6T
 

Yes, indeed. Makes for a very stable operation. More discussion (and some ideas) can be found here: http://www.nd6t.com/bitx/tuning
73,
Don

Jack, W8TEE
 

Interesting read, Don. FWIT, I'm working on Hans CAT control for the QCX and it uses 2 encoders; one for frequency changes and one for menu field changes. I the picture below:

Inline image

the Menu encoder is being used to turn the RIT on or off. (There's a "fly speck" bug where a couple of pixels aren't being turned on. It's fixed, but I haven't re-shot the picture.) The active VFO is shown in green. (Crappy picture, but all I have at the moment.)  The "RX" dot turns to a red  "TX" during transmit. The CAT is directional in that changes on the CAT device change the QCX, but if you change the QCX (e.g., use its encoder to change frequency) and that change is reflected on the CAT device. The two encoders are "switchless", working in conjunction with NO push button switches. Also, rather than using another encoder to change the frequency increment, I use another NO switch where a presses moves the increment to the left. (You can see the cursor as a white line under the 100's digit between the two frequencies. If the cursor is under the 10000Hz digit, another press "wraps" it back to the 100's digit. These limits are user-defined. I've done other projects where I used the encoder switch to do this, but I've moved away from this for the reasons explained below.

Two things this project has taught me about encoders: First, while working on this project, I've thrown away two out of four encoders because they were "intermittently" faulty. Since my EE skills suck, it took me an embarrassingly long period of time to find that "bug" because I assumed the bug was in my code. These were "switchless" encoders from China. This is one of those Penny-wise-Pound-foolish lessons to me. Second, I think I'm done with encoders that have shaft switches. My experience is that most QRP rigs don't have enough mass to let you use those switches without using the other hand to hold the rig during a switch press, even with non-skid feet in place. Instead, I'm using "paired" NO push button switches. I can activate these with a light touch without using the other hand.

The take away from this: Spend a few cents more, buy quality encoder (e.g., Bourns) from a reputable dealer.

Jack, W8TEE

On Wednesday, February 19, 2020, 7:30:32 AM EST, Don, ND6T via Groups.Io <nd6t_6@...> wrote:


Yes, indeed. Makes for a very stable operation. More discussion (and some ideas) can be found here: http://www.nd6t.com/bitx/tuning
73,
Don

--
Jack, W8TEE

N6QWHAM@...
 

Here is my two cents... Jack is right about getting a good Bourns encoder; but a couple of things to look at in addition to just being a Bourns. Look at the PPR (Pulses Per Revolution). Lower is better! I once bought an encoder with 512 PPR. You just looked at the encoder and it would move frequency. Something in the range of 20 to 30 PPR. Following that 20PPR would give e slower tuning feel. Avoid the kinds with "detents" --the clicking will drive you bonkers!

Second point to look for is the MTBF. (Mean Time Before Failure). Some encoders are only good for 20K revolutions while the Bourns line typically are rated at 100K. Another point on the Bourns is the wiring. Many mechanical encoders use the center pin as Ground. The left hand Pin with the shaft facing you is Ground on he Bourns.

Digikey sells the Bourns with the above features in the $1.50 range -- and if you buy 10 I think there is a price break. You can never have enough encoders.

Also -- do not be afraid of "rolling your own" substitute Raduino -- with just a bit of Arduino magic you can make it LSB and USB capable without touching the BFO crystal. This has some charm in that you can work FT-8 on 40 Meters with your Bitx40.

73's
Pete N6QW

Jack, W8TEE
 

Pete:

The "detents" are a personal choice. Most people like "detentless" encoders because those feel like a "normal" tuning knob in a rig. I suspect some of these commerical encoders are optical, which is more expensive. However, I actually prefer detents. I cannot hear them--don't know if this is because of ancient ears or they're just not that noisy--but I, instead, "feel" the detents. I like this because tuning stops when I release the knob. All of us have used radios where the tuning "coasts" a bit after releasing it. That coasting really irritates me, especially when checking in on a net. My old FT-1200 was really bad at that, one of the reasons I sold it. Coasting doesn't happen with detents and I like that.

I agree that anything between 16 and 24 PPR is a good choice. As you might guess, I buy 10x encoders at a time...just makes sense with shipping costs what they are. I'm buying more stuff domestically, mainly because of delivery delays. However, China has caught on to the "Show NA only" and seem to be drop-shipping to the US so they show up in an NA search. I've had NA searches result in items that would not be delivered for 6 weeks...obviously a drop-ship.

Good advice on the encoder pins. When you order, look at the spec sheet and perhaps even print out the "pin image", cut it out, and write on it the re-order info, and place it in your encoder parts bin.

Jack, W8TEE

On Wednesday, February 19, 2020, 9:34:14 AM EST, N6QWHAM@... <n6qwham@...> wrote:


Here is my two cents... Jack is right about getting a good Bourns encoder; but a couple of things to look at in addition to just being a Bourns. Look at the PPR (Pulses Per Revolution). Lower is better! I once bought an encoder with 512 PPR. You just looked at the encoder and it would move frequency. Something in the range of 20 to 30 PPR. Following that 20PPR would give e slower tuning feel. Avoid the kinds with "detents" --the clicking will drive you bonkers!

Second point to look for is the MTBF. (Mean Time Before Failure). Some encoders are only good for 20K revolutions while the Bourns line typically are rated at 100K. Another point on the Bourns is the wiring. Many mechanical encoders use the center pin as Ground. The left hand Pin with the shaft facing you is Ground on he Bourns.

Digikey sells the Bourns with the above features in the $1.50 range -- and if you buy 10 I think there is a price break. You can never have enough encoders.

Also -- do not be afraid of "rolling your own" substitute Raduino -- with just a bit of Arduino magic you can make it LSB and USB capable without touching the BFO crystal. This has some charm in that you can work FT-8 on 40 Meters with your Bitx40.

73's
Pete N6QW

--
Jack, W8TEE

Dennis Zabawa
 

I will throw in another vote for detents.  I have several electronic devices in the house that have detented encoders and they work well IMHO.

Arv Evans
 

The initial question was "whether the uBITX v3 used a pot or encoder for tuning".    Topic drift has changed
the focus from that question to which types of rotary encoders are best.

Getting back to the original question...I have am early version uBITX v3 and it has an encoder.  But my probably
faulty memory is telling me that there was a pot-tuned version of the BITX-40 that preceded the uBITX v3. 


Arv
_._


On Wed, Feb 19, 2020 at 7:34 AM <N6QWHAM@...> wrote:
Here is my two cents... Jack is right about getting a good Bourns encoder; but a couple of things to look at in addition to just being a Bourns. Look at the PPR (Pulses Per Revolution). Lower is better! I once bought an encoder with 512 PPR. You just looked at the encoder and it would move frequency. Something in the range of 20 to 30 PPR. Following that 20PPR would give e slower tuning feel. Avoid the kinds with "detents" --the clicking will drive you bonkers!

Second point to look for is the MTBF. (Mean Time Before Failure). Some encoders are only good for 20K revolutions while the Bourns line typically are rated at 100K. Another point on the Bourns is the wiring. Many mechanical encoders use the center pin as Ground. The left hand Pin with the shaft facing you is Ground on he Bourns.

Digikey sells the Bourns with the above features in the $1.50 range -- and if you buy 10 I think there is a price break. You can never have enough encoders.

Also -- do not be afraid of "rolling your own" substitute Raduino -- with just a bit of Arduino magic you can make it LSB and USB capable without touching the BFO crystal. This has some charm in that you can work FT-8 on 40 Meters with your Bitx40.

73's
Pete N6QW

Alan de G1FXB
 

ONLY if the sole function is VFO tuning then a smooth encoder is nice.
If it has a second function of navigating a menu structure, then with DETENTS otherwise you are overshoot and for always tickling the knob up / down to select the correct entry
only to depress the enter button on the encoder shaft and and it moves to the next line again at the last minute.....

Only trying to refuel your auto to an exact $ is more satisfying.


Alan


On 19/02/2020 18:49, Dennis Zabawa wrote:
I will throw in another vote for detents.  I have several electronic devices in the house that have detented encoders and they work well IMHO.

-- 
Smell Czech corruptions are inevitable

Arv Evans
 

Correction...even I could not get it right!    8-(
The original question was whether the BITX40 used a pot or encoder for tuning
Documentation on the HFSigs site indicates that the BITX-40 used a linear pot for
tuning. 


Arv
_._




On Wed, Feb 19, 2020 at 11:54 AM Arv Evans via Groups.Io <arvid.evans=gmail.com@groups.io> wrote:
The initial question was "whether the uBITX v3 used a pot or encoder for tuning".    Topic drift has changed
the focus from that question to which types of rotary encoders are best.

Getting back to the original question...I have am early version uBITX v3 and it has an encoder.  But my probably
faulty memory is telling me that there was a pot-tuned version of the BITX-40 that preceded the uBITX v3. 


Arv
_._


On Wed, Feb 19, 2020 at 7:34 AM <N6QWHAM@...> wrote:
Here is my two cents... Jack is right about getting a good Bourns encoder; but a couple of things to look at in addition to just being a Bourns. Look at the PPR (Pulses Per Revolution). Lower is better! I once bought an encoder with 512 PPR. You just looked at the encoder and it would move frequency. Something in the range of 20 to 30 PPR. Following that 20PPR would give e slower tuning feel. Avoid the kinds with "detents" --the clicking will drive you bonkers!

Second point to look for is the MTBF. (Mean Time Before Failure). Some encoders are only good for 20K revolutions while the Bourns line typically are rated at 100K. Another point on the Bourns is the wiring. Many mechanical encoders use the center pin as Ground. The left hand Pin with the shaft facing you is Ground on he Bourns.

Digikey sells the Bourns with the above features in the $1.50 range -- and if you buy 10 I think there is a price break. You can never have enough encoders.

Also -- do not be afraid of "rolling your own" substitute Raduino -- with just a bit of Arduino magic you can make it LSB and USB capable without touching the BFO crystal. This has some charm in that you can work FT-8 on 40 Meters with your Bitx40.

73's
Pete N6QW

Jerry Gaffke
 

Yes, a linear 10k pot for tuning the Bitx40.

Original surface mount Bitx40 used a 10k linear pot on a varactor diode for tuning.
Same as Bitx stuff going all the way back to the creation event, which occurred in 2004.
Farhan has done his best to add the mystique of mystery to Bitx origins by taking that site down,
but fortunately this little corner of history it is not yet totally lost to bitrot:
   https://web.archive.org/web/20040803214952/http://phonestack.com/farhan/bitx.html

Lots and lots of variations on the Bitx that we won't go into, most are documented in this forum.
The analog VFO was kind of drifty, so many were hacking in digital VFO's of various sorts.
In Dec 2016 the Bitx40 started shipping from HFSignals with the Raduino implementing a digital VFO:
    https://groups.io/g/BITX20/message/19177
The Bitx40's Raduino also used a 10k linear pot, now read by an ATMega328P's ADC pin.

Once the Bitx40 came out with the Raduino, there were no further changes to the Bitx40
as shipped from HFSignals till it was discontinued in 2019.  Though plenty of folks in the forum
hacked support for an encoder into the firmware to replace the 10k pot.

Arv, I'd think you're old enough to remember this stuff!
Or maybe you're old enough to forget it?

Jerry, KE7ER


On Wed, Feb 19, 2020 at 11:08 AM, Arv Evans wrote:
Correction...even I could not get it right!    8-(
The original question was whether the BITX40 used a pot or encoder for tuning
Documentation on the HFSigs site indicates that the BITX-40 used a linear pot for
tuning. 
 
 
Arv
_._

Arv Evans
 

Jerry

At 78 I seem to be forgetting more an more as the years drift by.  Some of the forgetting is
deliberate, but some is not.   8-(

Arv
_._


On Wed, Feb 19, 2020 at 1:38 PM Jerry Gaffke via Groups.Io <jgaffke=yahoo.com@groups.io> wrote:
Yes, a linear 10k pot for tuning the Bitx40.

Original surface mount Bitx40 used a 10k linear pot on a varactor diode for tuning.
Same as Bitx stuff going all the way back to the creation event, which occurred in 2004.
Farhan has done his best to add the mystique of mystery to Bitx origins by taking that site down,
but fortunately this little corner of history it is not yet totally lost to bitrot:
   https://web.archive.org/web/20040803214952/http://phonestack.com/farhan/bitx.html

Lots and lots of variations on the Bitx that we won't go into, most are documented in this forum.
The analog VFO was kind of drifty, so many were hacking in digital VFO's of various sorts.
In Dec 2016 the Bitx40 started shipping from HFSignals with the Raduino implementing a digital VFO:
    https://groups.io/g/BITX20/message/19177
The Bitx40's Raduino also used a 10k linear pot, now read by an ATMega328P's ADC pin.

Once the Bitx40 came out with the Raduino, there were no further changes to the Bitx40
as shipped from HFSignals till it was discontinued in 2019.  Though plenty of folks in the forum
hacked support for an encoder into the firmware to replace the 10k pot.

Arv, I'd think you're old enough to remember this stuff!
Or maybe you're old enough to forget it?

Jerry, KE7ER


On Wed, Feb 19, 2020 at 11:08 AM, Arv Evans wrote:
Correction...even I could not get it right!    8-(
The original question was whether the BITX40 used a pot or encoder for tuning
Documentation on the HFSigs site indicates that the BITX-40 used a linear pot for
tuning. 
 
 
Arv
_._

Jerry Gaffke
 

Arv,

Here's something you'll want to remember:  You just know too much
   https://www.agingcare.com/articles/seniors-brains-slower-because-of-too-much-information-167093.htm

Jerry, KE7ER


On Wed, Feb 19, 2020 at 12:54 PM, Arv Evans wrote:
Jerry
 
At 78 I seem to be forgetting more an more as the years drift by.  Some of the forgetting is
deliberate, but some is not.   8-(
 
Arv

Jim Willis
 

I’ve been running at 0.77 MHz for some time.

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Jerry Gaffke via Groups.Io
Sent: Wednesday, February 19, 2020 4:25 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Bitx 40 raduino pot or encoder?

 

Arv,

Here's something you'll want to remember:  You just know too much
   https://www.agingcare.com/articles/seniors-brains-slower-because-of-too-much-information-167093.htm

Jerry, KE7ER

On Wed, Feb 19, 2020 at 12:54 PM, Arv Evans wrote:

Jerry

 

At 78 I seem to be forgetting more an more as the years drift by.  Some of the forgetting is

deliberate, but some is not.   8-(

 

Arv

Jack, W8TEE
 

Jerry:

Reminds me of my recent physical when the doctor said I was gaining weight (true, partly because of some knee issues, partly because I eat too much). I said:

    I'm not fat. I'm just easy to see.

Without losing a beat, he said:

   Well, the next time we meet I want to see less of you.

Jack, W8TEE


On Wednesday, February 19, 2020, 4:34:54 PM EST, Jim Willis <jimwill172@...> wrote:


I’ve been running at 0.77 MHz for some time.

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Jerry Gaffke via Groups.Io
Sent: Wednesday, February 19, 2020 4:25 PM
To: BITX20@groups.io
Subject: Re: [BITX20] Bitx 40 raduino pot or encoder?

 

Arv,

Here's something you'll want to remember:  You just know too much
   https://www.agingcare.com/articles/seniors-brains-slower-because-of-too-much-information-167093.htm

Jerry, KE7ER

On Wed, Feb 19, 2020 at 12:54 PM, Arv Evans wrote:

Jerry

 

At 78 I seem to be forgetting more an more as the years drift by.  Some of the forgetting is

deliberate, but some is not.   8-(

 

Arv


--
Jack, W8TEE

Arv Evans
 

Jerry

Interesting, and a handy excuse (I just know too much!).  8-)

Arv
_._


On Wed, Feb 19, 2020 at 2:25 PM Jerry Gaffke via Groups.Io <jgaffke=yahoo.com@groups.io> wrote:
Arv,

Here's something you'll want to remember:  You just know too much
   https://www.agingcare.com/articles/seniors-brains-slower-because-of-too-much-information-167093.htm

Jerry, KE7ER

On Wed, Feb 19, 2020 at 12:54 PM, Arv Evans wrote:
Jerry
 
At 78 I seem to be forgetting more an more as the years drift by.  Some of the forgetting is
deliberate, but some is not.   8-(
 
Arv

Dean Souleles
 

Gents - 

I'm *only* 60 and already have challenges....

As far as tuning behavior fast or slow, increment or now, and encoder detents or no-detents, my feeling is this:  I prefer Zebras white with black stripes, others prefer black with white stripes.  Different horses for different courses. 

That is the beauty of the Arduino VFO -  a couple of lines of code and you can have it any way you like.

73 and cheers to all,

Dean
KK4DAS
(Every time I type my call, the first time I type it, it comes out KK$DAS.   I kind of like that.)