Date   
Re: Ref:Hilltopper 20 Manual, J5 and J6 headers

Charles W. Powell
 

Eric,

J5 is for programming the ATmega328 and for I/O if you add the CAT control code, and J6 is for display, if you care to add it.  I can send you the info privately, off list if you want it.  There are several versions of the firmware around; I adapted it for my own use with some minor cosmetic changes.  (I’m not much of a coder - I just do a few doodles here and there.)

Great little radio.  I just built my second HT-20 and it puts out just shy of 7 watts!  With the audio mods, there is more than enough volume generally with the gain pot about half-way up.  I may change the sidetone resistor - again.  I still find the sidetone to be a bit loud for my taste.

72,

Chas - NK8O

On Apr 30, 2019, at 8:35 PM, Eric Holzapfel <ewholz@...> wrote:

I have joined this group, very informative. I have just obtained a Hilltopper 20, and cannot find the section mentioned
in the manual about J5 and J6 - I have headers for this, but cannot find the info referenced in the manual
Online Support: Search for ‘Groups.io’ on your browser and register to use their free service. Find ‘4SQRP.groups.io and register to join. Once approved, find the HilltopperKit subgroup and register for it in turn. This is a group e-mail reflector and supports images and other file types. Please note that the J5 and J6 header strips are not provided in this kit- See the ‘Files’ section of the subgroup for more information.

Where is the files section? Is it possible to use the I2C pins (J5??) to show the freq??? Any info will help.

Thanks
eholz1

Ref:Hilltopper 20 Manual, J5 and J6 headers

Eric Holzapfel <ewholz@...>
 

I have joined this group, very informative. I have just obtained a Hilltopper 20, and cannot find the section mentioned
in the manual about J5 and J6 - I have headers for this, but cannot find the info referenced in the manual
Online Support: Search for ‘Groups.io’ on your browser and register to use their free service. Find ‘4SQRP.groups.io and register to join. Once approved, find the HilltopperKit subgroup and register for it in turn. This is a group e-mail reflector and supports images and other file types. Please note that the J5 and J6 header strips are not provided in this kit- See the ‘Files’ section of the subgroup for more information.

Where is the files section? Is it possible to use the I2C pins (J5??) to show the freq??? Any info will help.

Thanks
eholz1

Re: Measuring power

WA4EFS
 

Thanks for the several informative replies re. RF power measurement.  With a fully charged 12 volt battery as power source and a 50 ohm resistive load my scope indicates 40 volts P-P from the Hilltopper 40, equating to 4 watts, which seems about right.  13.8 volts might produce an additional watt or two out.

 

73, -Lloyd

 

From: HilltopperKit@4SQRP.groups.io [mailto:HilltopperKit@4SQRP.groups.io] On Behalf Of WA0ITP
Sent: Wednesday, April 17, 2019 2:03 PM
To: HilltopperKit@4SQRP.groups.io
Subject: Re: [HilltopperKit] Measuring power

 

My personal favorite is (Vpp/2.8)^2/feedline R   This makes sense to me and is easy to remember.  Same as yours Chas. 

72 WAØITP
I love this radio stuff.
www.wa0itp.com
www.4sqrp.com

On 4/17/2019 9:03 AM, Charles W. Powell via Groups.Io wrote:

Lloyd,

 

I don’t know about anyone else, but I am measuring power on mine, key down, using a 50 ohm dummy load, and connecting my high impedance oscilloscope leads across the load.  The scope is a a Siglent 200 mHz scope, so it is measuring far away from the rolloff.  Using the peak-to-peak voltage, I make my calculation by deriving the RMS voltage, then using RMS-squared/resistance.  So with about 13.4 DC volts input, my peak output voltage on the HT-20 was 52 volts.  ((52 * 0.707/2)^2)/50 = 6.8 watts into 50 ohms.  I get approximately the same readings with my MFJ tuner’s power readout and also my QRP-o-meter, although I don’t expect those to be nearly as accurate.

 

Caveats:  I might be entirely wrong in my calculations and I might be missing some subtlety in making this calculation.

 

72,

 

Chas - NK8O



On Apr 17, 2019, at 8:29 AM, WA4EFS <himself@...> wrote:

 

Several posts have referred to the RF power output of QRP rigs including the Hilltopper, the relation to amplifier class, or to final transistor quality, etc.  I am curious as to how power is being measured or assessed in relation to various reports.

 

Thanks and 73, 

-Lloyd

 

 

Re: What are the chances this would happen twice?

Charles W. Powell
 

That’s a difficult question. Where I live (near Kansas City) static discharge is rarely an issue. We have fairly high humidity, and I typically work in my basement. Static damage is always a possibility, but the BS170 is supposed to be pretty tough.

Chas - NK8O

On Apr 18, 2019, at 8:22 AM, Curt via Groups.Io <rhulett1=consolidated.net@groups.io> wrote:

Am curious whether the BS170 is as prone to damage from static as have heard the 2N7000 is. Somehow had the impression it was more rugged, but not sure where that impression came from,

Understanding that cumulative static damage happens before we receive parts, am paranoid assembling with FETs of any variety. The assembly is done in an aluminum tray, the FET goes immediately from the antistatic bag into the board. I use a grounded wrist strap, if the humidity is very low then assemble other components and wait for another day.

Curt KB5JO

Re: What are the chances this would happen twice?

Curt
 

Am curious whether the BS170 is as prone to damage from static as have heard the 2N7000 is. Somehow had the impression it was more rugged, but not sure where that impression came from,

  Understanding that cumulative static damage happens before we receive parts, am paranoid assembling with FETs of any variety.  The assembly is done in an aluminum tray, the FET goes immediately from the antistatic bag into the board.  I use a grounded wrist strap, if the humidity is very low then assemble other components and wait for another day.

Curt KB5JO

Re: Measuring power

WA0ITP
 

My personal favorite is (Vpp/2.8)^2/feedline R   This makes sense to me and is easy to remember.  Same as yours Chas. 
72 WAØITP
I love this radio stuff.
www.wa0itp.com
www.4sqrp.com
On 4/17/2019 9:03 AM, Charles W. Powell via Groups.Io wrote:

Lloyd,

I don’t know about anyone else, but I am measuring power on mine, key down, using a 50 ohm dummy load, and connecting my high impedance oscilloscope leads across the load.  The scope is a a Siglent 200 mHz scope, so it is measuring far away from the rolloff.  Using the peak-to-peak voltage, I make my calculation by deriving the RMS voltage, then using RMS-squared/resistance.  So with about 13.4 DC volts input, my peak output voltage on the HT-20 was 52 volts.  ((52 * 0.707/2)^2)/50 = 6.8 watts into 50 ohms.  I get approximately the same readings with my MFJ tuner’s power readout and also my QRP-o-meter, although I don’t expect those to be nearly as accurate.

Caveats:  I might be entirely wrong in my calculations and I might be missing some subtlety in making this calculation.

72,

Chas - NK8O

On Apr 17, 2019, at 8:29 AM, WA4EFS <himself@...> wrote:

Several posts have referred to the RF power output of QRP rigs including the Hilltopper, the relation to amplifier class, or to final transistor quality, etc.  I am curious as to how power is being measured or assessed in relation to various reports.
 
Thanks and 73, 
-Lloyd


Re: Measuring power

chuck adams <chuck.adams.k7qo@...>
 

You can save a few steps on the calculator by using  P = V_pk^2/100 for a 50 ohm load.
Always saves my bacon on a calculator.  Formula works only for 50 ohm load.

You can get the above formula from yours below by replacing  0.707/2 by  1/sqrt(2),
thus (0.707/2)^2 = 1/2 and (1/2)/50 = 1/100.  For those that missed that day of
class.  :-)

FYI

chuck, k7qo


On 4/17/19 7:03 AM, Charles W. Powell via Groups.Io wrote:
Lloyd,

I don’t know about anyone else, but I am measuring power on mine, key down, using a 50 ohm dummy load, and connecting my high impedance oscilloscope leads across the load.  The scope is a a Siglent 200 mHz scope, so it is measuring far away from the rolloff.  Using the peak-to-peak voltage, I make my calculation by deriving the RMS voltage, then using RMS-squared/resistance.  So with about 13.4 DC volts input, my peak output voltage on the HT-20 was 52 volts.  ((52 * 0.707/2)^2)/50 = 6.8 watts into 50 ohms.  I get approximately the same readings with my MFJ tuner’s power readout and also my QRP-o-meter, although I don’t expect those to be nearly as accurate.

Caveats:  I might be entirely wrong in my calculations and I might be missing some subtlety in making this calculation.

72,

Chas - NK8O

On Apr 17, 2019, at 8:29 AM, WA4EFS <himself@...> wrote:

Several posts have referred to the RF power output of QRP rigs including the Hilltopper, the relation to amplifier class, or to final transistor quality, etc.  I am curious as to how power is being measured or assessed in relation to various reports.
 
Thanks and 73, 
-Lloyd


Re: Measuring power

KB9BVN - <kb9bvn@...>
 

If I measure my HT20 into a dummy load with my WM2 power meter, I see close to 7 watts.  Perfect situation. 

If I measure my HT20 into my attic dipole thru my MFJ antenna tuner, I see close to 5 watts. Imperfect situation. 

My attic dipole is a halfwave 40m dipole...so tuning it up on 20m is not real efficient anyway. 






On Wed, Apr 17, 2019 at 10:03 AM Charles W. Powell via Groups.Io <doctorcwp=yahoo.com@groups.io> wrote:
Lloyd,

I don’t know about anyone else, but I am measuring power on mine, key down, using a 50 ohm dummy load, and connecting my high impedance oscilloscope leads across the load.  The scope is a a Siglent 200 mHz scope, so it is measuring far away from the rolloff.  Using the peak-to-peak voltage, I make my calculation by deriving the RMS voltage, then using RMS-squared/resistance.  So with about 13.4 DC volts input, my peak output voltage on the HT-20 was 52 volts.  ((52 * 0.707/2)^2)/50 = 6.8 watts into 50 ohms.  I get approximately the same readings with my MFJ tuner’s power readout and also my QRP-o-meter, although I don’t expect those to be nearly as accurate.

Caveats:  I might be entirely wrong in my calculations and I might be missing some subtlety in making this calculation.

72,

Chas - NK8O

On Apr 17, 2019, at 8:29 AM, WA4EFS <himself@...> wrote:

Several posts have referred to the RF power output of QRP rigs including the Hilltopper, the relation to amplifier class, or to final transistor quality, etc.  I am curious as to how power is being measured or assessed in relation to various reports.
 
Thanks and 73, 
-Lloyd



--
73 de KB9BVN
Brian Murrey

Re: Measuring power

Charles W. Powell
 

Lloyd,

I don’t know about anyone else, but I am measuring power on mine, key down, using a 50 ohm dummy load, and connecting my high impedance oscilloscope leads across the load.  The scope is a a Siglent 200 mHz scope, so it is measuring far away from the rolloff.  Using the peak-to-peak voltage, I make my calculation by deriving the RMS voltage, then using RMS-squared/resistance.  So with about 13.4 DC volts input, my peak output voltage on the HT-20 was 52 volts.  ((52 * 0.707/2)^2)/50 = 6.8 watts into 50 ohms.  I get approximately the same readings with my MFJ tuner’s power readout and also my QRP-o-meter, although I don’t expect those to be nearly as accurate.

Caveats:  I might be entirely wrong in my calculations and I might be missing some subtlety in making this calculation.

72,

Chas - NK8O

On Apr 17, 2019, at 8:29 AM, WA4EFS <himself@...> wrote:

Several posts have referred to the RF power output of QRP rigs including the Hilltopper, the relation to amplifier class, or to final transistor quality, etc.  I am curious as to how power is being measured or assessed in relation to various reports.
 
Thanks and 73, 
-Lloyd

Measuring power

WA4EFS
 

Several posts have referred to the RF power output of QRP rigs including the Hilltopper, the relation to amplifier class, or to final transistor quality, etc.  I am curious as to how power is being measured or assessed in relation to various reports.

 

Thanks and 73,

-Lloyd

 

Re: What are the chances this would happen twice?

Charles W. Powell
 

Just lucky, I guess!

Chas

On Apr 16, 2019, at 11:28 AM, Jim Pruitt <jpruitt67@...> wrote:

The BS170's that I am putting in the Hilltopper kits was purchased from Digikey and in one order so the lot number should be the same for all of the BS170's being supplied in the Hilltopper kits. I have not had any other reports of bad BS170's in the kits.

Thank you.

Jim Pruitt
WA7DUY

Re: What are the chances this would happen twice?

Jim Pruitt
 

The BS170's that I am putting in the Hilltopper kits was purchased from Digikey and in one order so the lot number should be the same for all of the BS170's being supplied in the Hilltopper kits.  I have not had any other reports of bad BS170's in the kits.

Thank you.

Jim Pruitt
WA7DUY


On 4/16/2019 9:08 AM, Charles W. Powell via Groups.Io wrote:
I will look Tim.  Interesting though that this HT-20 puts out 6.9 watts measured on my scope into 50 ohms, using the same lot of BS170s.  The MOSFETs were whatever was supplied with the kit, but my replacement for the HT-20 was a brand-name from DigiKey.

72,

Chas

On Apr 16, 2019, at 10:34 AM, Tim McDonough N9PUZ <tim.n9puz@...> wrote:

I'm curious, were the bad BS170 parts you discovered generic, no-name parts or were they marked from a major semiconductor house?

Tim N9PUZ

On Tue, Apr 16, 2019 at 10:23 AM Charles W. Powell via Groups.Io <doctorcwp=yahoo.com@groups.io> wrote:
Well, it did happen twice.  I replaced Q1, the BS170 that switches (mutes) on transmit, and I have normal receive audio now.

I bought a few extra BS170s so I think I may look at the PA in my HT 30 as well.  There's no reason that it should only put out 3 watts when all of the other HTs I've built put out more than 5 watts.

72,

Chas - NK8O

Re: What are the chances this would happen twice?

Charles W. Powell
 

I will look Tim.  Interesting though that this HT-20 puts out 6.9 watts measured on my scope into 50 ohms, using the same lot of BS170s.  The MOSFETs were whatever was supplied with the kit, but my replacement for the HT-20 was a brand-name from DigiKey.

72,

Chas

On Apr 16, 2019, at 10:34 AM, Tim McDonough N9PUZ <tim.n9puz@...> wrote:

I'm curious, were the bad BS170 parts you discovered generic, no-name parts or were they marked from a major semiconductor house?

Tim N9PUZ

On Tue, Apr 16, 2019 at 10:23 AM Charles W. Powell via Groups.Io <doctorcwp=yahoo.com@groups.io> wrote:
Well, it did happen twice.  I replaced Q1, the BS170 that switches (mutes) on transmit, and I have normal receive audio now.

I bought a few extra BS170s so I think I may look at the PA in my HT 30 as well.  There's no reason that it should only put out 3 watts when all of the other HTs I've built put out more than 5 watts.

72,

Chas - NK8O


Re: What are the chances this would happen twice?

Tim N9PUZ
 

I'm curious, were the bad BS170 parts you discovered generic, no-name parts or were they marked from a major semiconductor house?

Tim N9PUZ


On Tue, Apr 16, 2019 at 10:23 AM Charles W. Powell via Groups.Io <doctorcwp=yahoo.com@groups.io> wrote:
Well, it did happen twice.  I replaced Q1, the BS170 that switches (mutes) on transmit, and I have normal receive audio now.

I bought a few extra BS170s so I think I may look at the PA in my HT 30 as well.  There's no reason that it should only put out 3 watts when all of the other HTs I've built put out more than 5 watts.

72,

Chas - NK8O

Re: What are the chances this would happen twice?

Charles W. Powell
 

Well, it did happen twice.  I replaced Q1, the BS170 that switches (mutes) on transmit, and I have normal receive audio now.

I bought a few extra BS170s so I think I may look at the PA in my HT 30 as well.  There's no reason that it should only put out 3 watts when all of the other HTs I've built put out more than 5 watts.

72,

Chas - NK8O

Re: What are the chances this would happen twice?

Tim N9PUZ
 

Good grief. Not to wish ill fortune on you Charles but I hope you're just "lucky"!

Wonder if the group has had other reports of failures?

Tim N9PUZ

On 4/14/2019 2:41 PM, Charles W. Powell via Groups.Io wrote:
I built the Hilltoppers 20 I got at Ozarkcon and it went together well.  The transmitter puts out almost 6 watts.  But in trying to check the receiver, it acted like it was muted.  I encountered this same problem with the HT I modified for 30 meters and I found Q1 was bad.  I had sidetone audio and annunciator on the HT-20 that was just completed.  Soooooo.... with similar behavior and no test equipment, I thought I would start with removing Q1.  Q1 does the switching to mute the receiver on transmit.  Voila!  The receiver came to life.

So this raises a couple of questions.  First, did we get some bad BS170 MOSFETs in the recent batches, or am I just lucky?  Second, with my modded HT-30 only putting out about 3 watts and all my other HTs putting out over 5 watts, do I have a bad BS170 in the finals of the HT-30?  Is there any way to check the finals without simply removing and substituting?  It doesn't look to me like there is any way to check them because everything is in parallel, so no way to isolate any single MOSFET.  Comments?

Final word would be to warn folks to watch out for problems with the BS170s.  I'm thinking it's probably just dumb luck I ended up with two bad MOSFETs, and both ending up in Q1.  But there may be others as well.

72,

Chas - NK8O

What are the chances this would happen twice?

Charles W. Powell
 

I built the Hilltoppers 20 I got at Ozarkcon and it went together well.  The transmitter puts out almost 6 watts.  But in trying to check the receiver, it acted like it was muted.  I encountered this same problem with the HT I modified for 30 meters and I found Q1 was bad.  I had sidetone audio and annunciator on the HT-20 that was just completed.  Soooooo.... with similar behavior and no test equipment, I thought I would start with removing Q1.  Q1 does the switching to mute the receiver on transmit.  Voila!  The receiver came to life.

So this raises a couple of questions.  First, did we get some bad BS170 MOSFETs in the recent batches, or am I just lucky?  Second, with my modded HT-30 only putting out about 3 watts and all my other HTs putting out over 5 watts, do I have a bad BS170 in the finals of the HT-30?  Is there any way to check the finals without simply removing and substituting?  It doesn't look to me like there is any way to check them because everything is in parallel, so no way to isolate any single MOSFET.  Comments?

Final word would be to warn folks to watch out for problems with the BS170s.  I'm thinking it's probably just dumb luck I ended up with two bad MOSFETs, and both ending up in Q1.  But there may be others as well.

72,

Chas - NK8O

Re: Hilltopper mod performance

Charles W. Powell
 

I had time this afternoon to complete the audio mod to my Hilltopper 30, by replacing R5 and C22.  It makes an audible difference, putting a signal at -107 dBm from faint to fair.  If i turned the RF gain down to where it is roughly minimum, I could still hear the -107 dBm signal input.  At full gain, it was noticeably louder, meaning there is at an absolute minimum 3 dB of audio gain, and probably more like 6 dB. I didn't measure it but you can hear a difference with a controlled input.  I tried again at 0 dBm to overload the audio.  It was L-O-U-D with the earbuds on the table, but no howl, no squeal, and no feedback.

Tip:  Solder R5 into place from the bottom of the board.  It's easier to get to it and it won't slide down through because its already secured by gravity.  If you are building for the first time it really keeps R5 out of the way of the pushbutton switch standoffs.

72,

Chas - NK8O

Re: Hilltopper mod performance

Dave Benson
 



Thanks, Chas!

If you've already got enough audio, you're done- the replacement IC is the 'biggie'

73- Dave


On Fri, Apr 12, 2019 at 7:49 AM Charles W. Powell via Groups.Io <doctorcwp=yahoo.com@groups.io> wrote:
I replaced the audio chip in one of my Hilltoppers last night and hooked it to the signal generator.  -73 dBm - great! -107 dBm, still great.  Then for the more difficult tests.  -33 dBm used to send the radio into its howling squeal.  I turned down the gain at -33 dBm and slowly turned up the RF gain.  So far, so good; no squeal.  So rinse and repeat at 0 dBm.  With the gain at full I couldn't leave the ear buds in place, but no squeal.  Next test: full RF gain with a sudden signal at 0 dBm.  NO SQUEAL.  Now I have to admit that I need to change out the RC combination, but I still don't expect any significant changes in performance.

Just for reference, I don't think input to any of my radios approaches 0 dBm even when my neighbor, 1 mile away, is transmitting at 1.5 kW into his phased arrays pointed right at me.  It's not an RF level you are likely to encounter in the real world.

Dave has come through for us again, making a great little radio even better.

72,

Chas - NK8O

Hilltopper mod performance

Charles W. Powell
 

I replaced the audio chip in one of my Hilltoppers last night and hooked it to the signal generator.  -73 dBm - great! -107 dBm, still great.  Then for the more difficult tests.  -33 dBm used to send the radio into its howling squeal.  I turned down the gain at -33 dBm and slowly turned up the RF gain.  So far, so good; no squeal.  So rinse and repeat at 0 dBm.  With the gain at full I couldn't leave the ear buds in place, but no squeal.  Next test: full RF gain with a sudden signal at 0 dBm.  NO SQUEAL.  Now I have to admit that I need to change out the RC combination, but I still don't expect any significant changes in performance.

Just for reference, I don't think input to any of my radios approaches 0 dBm even when my neighbor, 1 mile away, is transmitting at 1.5 kW into his phased arrays pointed right at me.  It's not an RF level you are likely to encounter in the real world.

Dave has come through for us again, making a great little radio even better.

72,

Chas - NK8O