Topics

RD16HHF1 power curve flattening...some

Ashhar Farhan
 

John,
You are right about the, Si5531. The way it panned out was that first there was the. Bitx40 with analog vfo. That was unstable for the digital modes, so we made the raduino. Then, because there was a raduino, the ubitx happened. 
Designing radios teaches you how to design them. Neither of the two radios was supposed to be all that they are doing now. This is purely the effort of you guys. Very often while searching for something on the net, the most relevant information is from people who have done something extraordinary with these radios. I continue my education.

-fa

On Mon, 2 Apr 2018, 05:22 John, <passionfruit88@...> wrote:
Dear Mr Farhan, 

Thank you for your post. I also personally think that 10 watts is is a good number and I have set my rig at just under that on 15 to 10M.

Unfortunately to get to this  power level, the lower bands have to be above.

In my case that value is 16 to 17W on 80M. sloping to 9W on 15m and flat after that despite the mods that have been described in this thread (its original objective) and in other threads. The original variation as-built was, from memory, 10 to 1W variation across 40-10M, or 17 to 2W at higher PA voltage.

I am working on an 1st If shift based ALC/power limiter using the technique described in my other post and this will hopefully allow for a completely flat power curve over the bands.

But unfortunately this is expected to only work in SSB modes.

So the issue remains that the power curve as designed is quite steep.

My wish for a future version of the uBitx is, if there is one, and I sincerely hope there is, for a somewhat flatter curve. A maximum variation of 1 to 2 for example would be in my opinion quite acceptable.

While we are on the wishes, it would have made my modifications much simpler if the Si5351 was on the main board as it would allow to extend the I2C bus to whatever micro-controller we wished to use.

Finally, a big thank you for such a wonderful rig. It is such a pleasure to work with, and its customisation makes it an unparalleled match for our own needs.

All the best,

73, John (VK2ETA)

Kees T
 

I personally prefer a max of ~10W also (battery power, etc) and the RD transistors are definitely intended for "RF" use and work great on 10m/15m (vs the 510s which essentially quit around 18MHz). I was wondering if anyone has tried the RD06HHF1 RF transistors ? 

73 Kees K5BCQ

Jerry Gaffke
 

A search for "si5351 main board" in this forum will show it's been suggested a half dozen times,
starting with post 20455.  I'm still hoping it will happen someday. 
Can ship with a Nano and perhaps a 2x16 i2c LCD so the rig is easy to get going, 
but also easy to move on to bigger and better processors and displays. 
Most of us can find plenty of uses for a spare Nano and LCD.

Of course, the current Raduino is nice in that it eliminates a wiring harness from Raduino to uBitx.
And I understand the wisdom of avoiding unnecessary changes once something works.

But I'd prefer the si5351 on the main board. 
And maybe pads for an optional ad8307, for use as an RF probe, s-meter, and sweeperino.

The $0.20 ad8307's on ebay apparently work just fine.
Search for "20pcs ad8307"

Jerry, KE7ER



On Sun, Apr 1, 2018 at 06:10 pm, Ashhar Farhan wrote:
You are right about the, Si5531. The way it panned out was that first there was the. Bitx40 with analog vfo. That was unstable for the digital modes, so we made the raduino. Then, because there was a raduino, the ubitx happened.     

On Mon, 2 Apr 2018, 05:22 John, <passionfruit88@...> wrote:
While we are on the wishes, it would have made my modifications much simpler if the Si5351 was on the main board as it would allow to extend the I2C bus to whatever micro-controller we wished to use.

John <passionfruit88@...>
 

Hello Jerry,

I understand the reasons why we are in the current configuration. It made sense.

These AD8307 are cheap log amps.

Thanks for the information.

73, John

James Lynes
 

My Bitx40 Raduino, now spare as I bought Mike's RaduinoX, is making a fine VFO for my 4SQRP ZZRX-40 DC receiver kit. I'm using Allard's v1.26 code with a few changes to make it tune 7.000 to 7.300 Mhz.

So, there are other uses for Raduinos with the si5351 onboard.

I wonder if there would still be tuning clicks with the si5351 onboard the uBitx?

James

Jose Amador
 

I agree 10 watts is good enough. It does not make sense from the
linearity, thermal and energy management to just gain half a true S
unit. Also, to "nail" the output to what you can get on 10 m, and
attenuate the drive on the lower bands, a piece of cake. To me, the
next logical step is at least 6 to 10 dB (40 100 watts). That is a job
for an external amplifier. 30 years ago 10 watts was good enough.
Nowadays cheap SWPSU have increased the noise floor 30 dB. The goal
should be to strive to lower that level of EMI pollution. You can't
work'em if you can't hear'em!

On 4/1/18, Ashhar Farhan <farhanbox@...> wrote:
How much power should we put out? It is really your call. I personally
prefer 10 watts. There are multiple reasons. First, between 10 watts and
20 watts, the other side will feel almost no difference. Second, at 10
watts, I can still you batteries. Third, the heatsink is managable.
Fourth, I am technically in QRP land.

- f


On Sunday 01 April 2018 09:03 AM, Nik VK4PLN wrote:
Hi John,
BN42-202, but a 2:4 ratio winding giving 1:4 transformation. Runs cool
at 20+w with 330pf Mica cap. 220ohm feedback resistor.
Listening on 14.277 ?
73 Nick

chris gress <Chrisg0wfh@...>
 

Would bn73-202 work with rd16hhf1 I got bn43-202 just getting the bits for the mod chris


On Mon, 2 Apr 2018, 16:58 Jose Amador, <jose.co2ja@...> wrote:
I agree 10 watts is good enough. It does not make sense from the
linearity, thermal and energy management to just gain half a true S
unit. Also, to "nail" the output to what you can get on 10 m, and
attenuate the drive on the lower bands, a piece of cake. To me, the
next logical step is at least 6 to 10 dB (40 100 watts). That is a job
for an external amplifier. 30 years ago 10 watts was good enough.
Nowadays cheap SWPSU have increased the noise floor 30 dB. The goal
should be to strive to lower that level of EMI pollution. You can't
work'em if you can't hear'em!

On 4/1/18, Ashhar Farhan <farhanbox@...> wrote:
> How much power should we put out? It is really your call. I personally
> prefer 10 watts. There are multiple reasons. First, between 10 watts and
> 20 watts, the other side will feel almost no difference. Second, at 10
> watts, I can still you batteries. Third, the heatsink is managable.
> Fourth, I am technically in QRP land.
>
> - f
>
>
> On Sunday 01 April 2018 09:03 AM, Nik VK4PLN wrote:
>> Hi John,
>> BN42-202, but a 2:4 ratio winding giving 1:4 transformation. Runs cool
>> at 20+w with 330pf Mica cap. 220ohm feedback resistor.
>> Listening on 14.277 ?
>> 73 Nick
>>
>
>



Thomas DD2TH
 

Hi everyone,

I tried to do this mod: https://ubitx.net/2018/02/16/power-amp-fix/

I checked everything for shorts, and a multimeter connected to the power input shows typical capacitor behaviour. However, when I connect power, my 3A fuse instantly pops. Is it possible that fake RD16HHF1 are causing this? I'm kinda desperate.

Heinz-W. Höfermann
 

I can say from the pic that the "RD16HHF1" are fakes! Had my share of buying those fake stuff.
Hannes, DL4AAJ 

Am 17.07.2018 um 18:30 schrieb fr.beckenbauer@...:

Hi everyone,

I tried to do this mod: https://ubitx.net/2018/02/16/power-amp-fix/

I checked everything for shorts, and a multimeter connected to the power input shows typical capacitor behaviour. However, when I connect power, my 3A fuse instantly pops. Is it possible that fake RD16HHF1 are causing this? I'm kinda desperate.


Ralph Mowery
 

I did this basic mod and it works fine for me.  

Try pulling the power plug going to the board.  There are 3 wires, one ground and 2 hot wires.  One of the hot wires goes directly to the finals and the other wire goes to everything else.  Disconnect the wire going to the finals and see if the fuse still blows.  If not, it could be fake parts , miswiring, or maybe you have shorted the cross over wires on the final.  I bought my finals from RF  parts. 

One other thought, did you cut the drive pot back  and rebias the finals with the other two pots ?  You may be driving it to more output or maybe the bias is set wrong.

de ku4pt


On Tue, Jul 17, 2018 at 12:30 PM, <fr.beckenbauer@...> wrote:
Hi everyone,

I tried to do this mod: https://ubitx.net/2018/02/16/power-amp-fix/

I checked everything for shorts, and a multimeter connected to the power input shows typical capacitor behaviour. However, when I connect power, my 3A fuse instantly pops. Is it possible that fake RD16HHF1 are causing this? I'm kinda desperate.


Clark Martin
 

Did you reroute the pins on the RD16HHF!, the are in a different arrangement than the IRF510.  The IRF510 is GDS, the RD16HHF1 is GSD.  Swapping the source and drain will blow the fuse like that.

Clark Martin
KK6ISP

On Jul 17, 2018, at 9:30 AM, fr.beckenbauer@... wrote:

Hi everyone,

I tried to do this mod: https://ubitx.net/2018/02/16/power-amp-fix/

I checked everything for shorts, and a multimeter connected to the power input shows typical capacitor behaviour. However, when I connect power, my 3A fuse instantly pops. Is it possible that fake RD16HHF1 are causing this? I'm kinda desperate.

Clark Martin
 

Okay, I just noticed the second photo and it does look like you have the source and drains swapped.  Might there be a short between them.  I’d check out each transistor for a short using a ohmmeter.  With the power cable to the board disconnected you should see an open circuit.


Clark Martin
KK6ISP

On Jul 17, 2018, at 1:42 PM, Clark Martin <kk6isp@...> wrote:

Did you reroute the pins on the RD16HHF!, the are in a different arrangement than the IRF510.  The IRF510 is GDS, the RD16HHF1 is GSD.  Swapping the source and drain will blow the fuse like that.

Clark Martin
KK6ISP

On Jul 17, 2018, at 9:30 AM, fr.beckenbauer@... wrote:

Hi everyone,

I tried to do this mod: https://ubitx.net/2018/02/16/power-amp-fix/

I checked everything for shorts, and a multimeter connected to the power input shows typical capacitor behaviour. However, when I connect power, my 3A fuse instantly pops. Is it possible that fake RD16HHF1 are causing this? I'm kinda desperate.

Kevin Rea
 

On Thu, Mar 8, 2018 at 05:14 PM, "John" <passionfruit88@...> wrote:
Hi John,
did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea

MVS Sarma
 

I too suspect the devices  OP bought.  He could remove them and test with a DMM for the correctness of pinout.
 
 I am currently depending for my RD hhf and hvf devices, on an ebay seller " polida2008" after having suffered fake ones from another seller.
 This seller is now operating with another seller name " 5hk1584 "
 While i have no business deal with this seller(s), I do enjoy genuine devices for my hobby.  Hope it helps.


Regards
MVS Sarma
 vu3zmv

On Wed, Jul 18, 2018 at 9:02 AM, Kevin Rea <reakevinscott@...> wrote:
On Thu, Mar 8, 2018 at 05:14 PM, "John" <passionfruit88@...> wrote:
Hi John,
did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea


Ashhar Farhan
 

Are you sure that the pins are not shorting? 


On Wed, 18 Jul 2018, 10:23 Mvs Sarma, <mvssarma@...> wrote:
I too suspect the devices  OP bought.  He could remove them and test with a DMM for the correctness of pinout.
 
 I am currently depending for my RD hhf and hvf devices, on an ebay seller " polida2008" after having suffered fake ones from another seller.
 This seller is now operating with another seller name " 5hk1584 "
 While i have no business deal with this seller(s), I do enjoy genuine devices for my hobby.  Hope it helps.


Regards
MVS Sarma
 vu3zmv

On Wed, Jul 18, 2018 at 9:02 AM, Kevin Rea <reakevinscott@...> wrote:
On Thu, Mar 8, 2018 at 05:14 PM, "John" <passionfruit88@...> wrote:
Hi John,
did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea


MVS Sarma
 

Farhan jee
 the "c" mark on the right of Logo indicates that devices are fake.If  IRF530  re labelled as indicated that they are fake. I had a bunch of therm. If some one doen't check under item details for a comment   "Make: generic / unbranded" They do get fake ones.

 if we get IRF530 or so re labelled as RD16, Obviously there would be a short , of course through the internal protection diode.

Regards
MVS Sarma
 

On Wed, Jul 18, 2018 at 11:13 AM, Ashhar Farhan <farhanbox@...> wrote:
Are you sure that the pins are not shorting? 

On Wed, 18 Jul 2018, 10:23 Mvs Sarma, <mvssarma@...> wrote:
I too suspect the devices  OP bought.  He could remove them and test with a DMM for the correctness of pinout.
 
 I am currently depending for my RD hhf and hvf devices, on an ebay seller " polida2008" after having suffered fake ones from another seller.
 This seller is now operating with another seller name " 5hk1584 "
 While i have no business deal with this seller(s), I do enjoy genuine devices for my hobby.  Hope it helps.


Regards
MVS Sarma
 vu3zmv

On Wed, Jul 18, 2018 at 9:02 AM, Kevin Rea <reakevinscott@...> wrote:
On Thu, Mar 8, 2018 at 05:14 PM, "John" <passionfruit88@...> wrote:
Hi John,
did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea



 

Some fake RD16HHF turned out to be IRF510 on my tester. The pin orientation was IRF and so was capacitance.
They worked fine in my B40 boards.

Raj


At 18-07-18, you wrote:
Farhan jee
 the "c" mark on the right of Logo indicates that devices are fake.If  IRF530  re labelled as indicated that they are fake. I had a bunch of therm. If some one doen't check under item details for a comment   "Make: generic / unbranded" They do get fake ones.

 if we get IRF530 or so re labelled as RD16, Obviously there would be a short , of course through the internal protection diode.

Regards
MVS Sarma
Â

On Wed, Jul 18, 2018 at 11:13 AM, Ashhar Farhan <farhanbox@...> wrote:
Are you sure that the pins are not shorting?Â

On Wed, 18 Jul 2018, 10:23 Mvs Sarma, <mvssarma@...> wrote:
I too suspect the devices  OP bought.  He could remove them and test with a DMM for the correctness of pinout.
Â
 I am currently depending for my RD hhf and hvf devices, on an ebay seller " polida2008" after having suffered fake ones from another seller.
 This seller is now operating with another seller name " 5hk1584 "
 While i have no business deal with this seller(s), I do enjoy genuine devices for my hobby.  Hope it helps.


Regards
MVS Sarma
 vu3zmv

On Wed, Jul 18, 2018 at 9:02 AM, Kevin Rea <reakevinscott@... > wrote:
On Thu, Mar 8, 2018 at 05:14 PM, "John" < passionfruit88@...> wrote:
Hi John,

did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea


Kevin Rea
 

How long does it take you to receive things from polida2008 ?

 

Kevin

 

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Ashhar Farhan
Sent: Tuesday, July 17, 2018 10:44 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some

 

Are you sure that the pins are not shorting? 

 

On Wed, 18 Jul 2018, 10:23 Mvs Sarma, <mvssarma@...> wrote:

I too suspect the devices  OP bought.  He could remove them and test with a DMM for the correctness of pinout.

 

 I am currently depending for my RD hhf and hvf devices, on an ebay seller " polida2008" after having suffered fake ones from another seller.

 This seller is now operating with another seller name " 5hk1584 "

 While i have no business deal with this seller(s), I do enjoy genuine devices for my hobby.  Hope it helps.

 


Regards
MVS Sarma

 vu3zmv

 

On Wed, Jul 18, 2018 at 9:02 AM, Kevin Rea <reakevinscott@...> wrote:

On Thu, Mar 8, 2018 at 05:14 PM, "John" <passionfruit88@...> wrote:

Hi John,

did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea

 

MVS Sarma
 

of course "snail mail shipping-- about 30 0r 40 days ti India but you might get faster  if in US.

Regards
MVS Sarma
 

On Thu, Jul 19, 2018 at 12:32 AM, Kevin Rea <reakevinscott@...> wrote:

How long does it take you to receive things from polida2008 ?

 

Kevin

 

 

From: BITX20@groups.io <BITX20@groups.io> On Behalf Of Ashhar Farhan
Sent: Tuesday, July 17, 2018 10:44 PM
To: BITX20@groups.io
Subject: Re: [BITX20] RD16HHF1 power curve flattening...some

 

Are you sure that the pins are not shorting? 

 

On Wed, 18 Jul 2018, 10:23 Mvs Sarma, <mvssarma@...> wrote:

I too suspect the devices  OP bought.  He could remove them and test with a DMM for the correctness of pinout.

 

 I am currently depending for my RD hhf and hvf devices, on an ebay seller " polida2008" after having suffered fake ones from another seller.

 This seller is now operating with another seller name " 5hk1584 "

 While i have no business deal with this seller(s), I do enjoy genuine devices for my hobby.  Hope it helps.

 


Regards
MVS Sarma

 vu3zmv

 

On Wed, Jul 18, 2018 at 9:02 AM, Kevin Rea <reakevinscott@...> wrote:

On Thu, Mar 8, 2018 at 05:14 PM, "John" <passionfruit88@...> wrote:

Hi John,

did you mount the new pot in the front or  back or just leave it on the breadboard ?
kevin rea
lancaster, calif.
k6rea