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RD16HHF1 in the uBITX #ubitx


 

HI Group.
I have been searching and reading topics with regards to using the RD16HHF1 in the uBITX.
So far I have only been able to find suggesstions, but no actual implementations...

I was testing my uBITX and getting 9w on 40m but only 1W at 10m...
Would love to have 5w + higher up.

Can anyone provide more info/help?

Thanks.
73, Nick VK4PLN


 

PA1FOX has done this, but I don't think he has
posted detailed results yet. (He has promised
to do so).

I have some, but have not gotten around to finding out what
they do. It looks very good, though.

john
AD5YE


M Garza
 

I am still waiting for mine.? Second order, last oder sat for over a week until I asked about them and was told they were out of stock...

So much for customer service.

Marco - KG5PRT?

On Feb 4, 2018 6:04 PM, "John Backo" <jabac@...> wrote:
PA1FOX has done this, but I don't think he has
posted detailed results yet. (He has promised
to do so).

I have some, but have not gotten around to finding out what
they do. It looks very good, though.

john
AD5YE




 

the Parts Place is a good place to get some. But they are now on back-order.

Also, it is noted that the prices have increased (~$US5.00 for RD16HHF1).
It looks like the market is catching up with what amateurs are realizing in
the capacity of these devices. Hi.

john
AD5YE


M Garza
 

That is where I placed my second order.? The other place was closer and I should have had them in a couple of days...? oh well.

Marco - KG5PRT?

On Feb 4, 2018 7:01 PM, "John Backo" <jabac@...> wrote:

the Parts Place is a good place to get some. But they are now on back-order.

Also, it is noted that the prices have increased (~$US5.00 for RD16HHF1).
It looks like the market is catching up with what amateurs are realizing in
the capacity of these devices. Hi.

john
AD5YE




 

NO cheap, but what about:
Like this:


73, Nick, VK4PLN


Dave Bottom
 

I got mine from RF Parts in 2 days around $5 each.??

I also got some of the RD16HVF1's (good through 2M) as well.? They were only a tiny bit more than the 30MHz HF parts (less than $6 as I recall).

I won't be trying these until I've had a chance to check out the driver stages 3.5-30 MHz, later this month when I return from a couple of trips.

Dave WI6R

On Sun, Feb 4, 2018 at 3:32 PM, Nick VK4PLN <nickpullen@...> wrote:
HI Group.
I have been searching and reading topics with regards to using the RD16HHF1 in the uBITX.
So far I have only been able to find suggesstions, but no actual implementations...

I was testing my uBITX and getting 9w on 40m but only 1W at 10m...
Would love to have 5w + higher up.

Can anyone provide more info/help?

Thanks.
73, Nick VK4PLN




--
73 Dave WI6R


 

Oh, just bite the bullet and go QR-Oh-Oh-Oh!! HiHi



73, David KB4FXC

On Sun, 4 Feb 2018, Dave Bottom wrote:

I got mine from RF Parts in 2 days around $5 each.

I also got some of the RD16HVF1's (good through 2M) as well. They were
only a tiny bit more than the 30MHz HF parts (less than $6 as I recall).

I won't be trying these until I've had a chance to check out the driver
stages 3.5-30 MHz, later this month when I return from a couple of trips.

Dave WI6R

On Sun, Feb 4, 2018 at 3:32 PM, Nick VK4PLN <nickpullen@...> wrote:

HI Group.
I have been searching and reading topics with regards to using the
*RD16HHF1* in the uBITX
*.*So far I have only been able to find suggesstions, but no actual
implementations...

I was testing my uBITX and getting 9w on 40m but only 1W at 10m...
Would love to have 5w + higher up.

Can anyone provide more info/help?

Thanks.
73, Nick VK4PLN




 

Well, it's nice. But you still have to design the amp.

And blowing up one of them is a whole lot more expensive. Hi.
Let's see...I could get about 42 RD16HXXX devices for every one
of these. And if I designed the rig properly, It should give out
over 400W.

Incidentally, the fact that prices are rising means that counterfeits
can't be far behind. It is so easy to take any MOSFET and erase
the number to claim it is something else. Caveat Emptor.

john
AD5YE


 

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Check this socket trick below that someone else posted.? Then fold the RD device over and screw it to the case.? Tab is not hot any more.? Re-bias.

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of K9HZ
Sent: Thursday, February 01, 2018 7:59 AM
To: [email protected]
Subject: [SPAM] Re: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

?

I really like that!?? If you fold the RD16 over you could use a heat sink out the back…

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Raj vu2zap
Sent: Thursday, February 01, 2018 4:24 AM
To: [email protected]
Subject: [SPAM] Re: [BITX20] Replacing the PA section on Bitx 40

?

Here is how I made the socket and mounted the RDD16

Note the RDD is reversed and? then the gate is actually soldered to the IRF gate line which goes behind the FET.
Now I can use either of them..

You will need to think of a heat sink plate that fits this way!

Emacs!

At 01/02/2018, you wrote:

Why replace everything??? You can probably put it in place of the 510 (making sure it is pinned correctly, of course).? ?
I am waiting on a pair, myself, that I will be stuffing into the ubitx.?? ? I want to even out the power output.?? I will also try a resistor/capacitor in parallel, in series with the gate, to try and even out the frequency response.?? I am thinking 4.7 ohm & 4700pf.?? I will also try 6.8 ohm & 4700pf.?? Depends on how flat I can get the output.

Marco - KG5PRT?

On Jan 31, 2018 10:12 PM, "James Lawrie" <lawriejk@...> wrote:

Hello,

My shipment of replacement RF Mosfets have arrived and I want to replace the on board PASection with one based on the RD16HHF1. It will be a separate small PCB based on the reference design shown in the data sheet. I need help from the professionals here as to where to attach the new PA board.

I know it would be somewhere after the 2N2219A driver, and I want to remove all bypassed SMTs and or other parts from the Bitx board in that area. If you have a pretty good idea could you please let me know, and possibly a drawing if you could. This should keep me busy and off the forum for a while.


 

Somebody already did the amp for you:
? ??

Unfortunately, it requires 2 or 3 watts going in for full output.
So we still have to bring the uBitx up a bit from 1W on 30m.

Jerry, KE7ER


On Sun, Feb 4, 2018 at 06:39 pm, John Backo wrote:
Well, it's nice. But you still have to design the amp.


 

I just wanna be able to output 5-10w on 28mhz.... not 1w... My QTH is pretty remote and without "decent" power, I wont get any contacts on >7mhz...

Might have to seriously consider an FT817, but the price.... lol.


 

Or a Youkits TJ5A


 

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Two RD16HHF1 parts replacing the 510’s will do that.

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Nick VK4PLN
Sent: Sunday, February 04, 2018 10:06 PM
To: [email protected]
Subject: [SPAM] Re: [BITX20] RD16HHF1 in the uBITX #ubitx

?

I just wanna be able to output 5-10w on 28mhz.... not 1w... My QTH is pretty remote and without "decent" power, I wont get any contacts on >7mhz...

Might have to seriously consider an FT817, but the price.... lol.


 

Excellent, thats what I am hoping to get to.
So the bias will need re-adjusting... Easy....?
What about the input and output transformers? I assume this will need modification due to the differnet impedances of the IRF and RD...

Thanks everyone for your input so far.
73.NIck VK4PLN


 

Ha! Re-designing the transformers is most of the tricky work. Yes; you will have to do that.
It might require some experimentation. Try to use FT-61 hog-nose material. I think it will be more
or less good for this application. FT-43 might work, but it will taper off at higher frequencies.

Keep the layout rather simple and try, if possible, to make it on a separate board with inputs and
outputs as far away from each other as possible. Some feedback mechanism between drain
and gate (or drain and ground) may be necessary. Simple attenuation impedance or transformer
matches should work for driving the gates, since the capacitance is quite low. Keep in mind the
WA2EBY layout and matching -- that should be a good guide.

I was thinking of setting the two output MOSFETS with 2N3866 drivers. Should put out about 10-14W
from 80m to 10m, with a drive of .5W or so...maybe less.

john
AD5YE


 

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Bill:?

Sometime ago I read about a transistor that can handle a 65:1 SER. Do you know anything about the device?



Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------
From: K9HZ <bill@...>
Date: 2/4/18 23:25 (GMT-05:00)
Subject: Re: [BITX20] RD16HHF1 in the uBITX #ubitx

Two RD16HHF1 parts replacing the 510’s will do that.

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – J68HZ

Soufriere, St. Lucia W.I.

Rent it:

Like us on Facebook!

?

?

email:? bill@...

?

From: [email protected] [mailto:[email protected]] On Behalf Of Nick VK4PLN
Sent: Sunday, February 04, 2018 10:06 PM
To: [email protected]
Subject: [SPAM] Re: [BITX20] RD16HHF1 in the uBITX #ubitx

?

I just wanna be able to output 5-10w on 28mhz.... not 1w... My QTH is pretty remote and without "decent" power, I wont get any contacts on >7mhz...

Might have to seriously consider an FT817, but the price.... lol.


 

Impressive.
But what's an SER?
When I google "transistor SER" all I get is a bunch of Spanish language pages.


On Sun, Feb 4, 2018 at 09:06 pm, Leland Lannoye wrote:
Sometime ago I read about a transistor that can handle a 65:1 SER. Do you know anything about the device?
?


Vince Vielhaber
 

He might be referring to the MRFE6VP61K25H/HS. Probably seen here:

Vince.

On 02/05/2018 01:23 AM, Jerry Gaffke via Groups.Io wrote:
Impressive.
But what's an SER?
When I google "transistor SER" all I get is a bunch of Spanish language
pages.

On Sun, Feb 4, 2018 at 09:06 pm, Leland Lannoye wrote:

Sometime ago I read about a transistor that can handle a 65:1 SER.
Do you know anything about the device?


--
Michigan VHF Corp.


 


>PA1FOX has done this, but I don't think he has

>posted detailed results yet. (He has promised
>to do so).

>I have some, but have not gotten around to finding out what
>they do. It looks very good, though.

>john
>AD5YE

Yep, correct. I'm still here :)
View for the receiver in action so far.

I've been messing around with RD16HHF1 and it looks promising. Due to lack of time I have not been able to finish the tests yet, but 10 watts at 17m is easy.

They seem far more robust as well. During the test phase of the IRF's I blew up a couple of them, but the RD16HHF1 has already suffered from my experiments (wrong output impedance etc) but has survived all. The gain of the RD is much higher at the upper frequencies compared to the IRF, so I have encountered some oscillations if the bias is set too high. It's not a big problem to deal with that. The efficiency at 80m is better than with the IRF but still not so good as 30 to 17m. I'm still working on that. Need to play around with the binocular toroid.
I also still need to finish the low pass filter for 15-10m to see what it will do there. The output power at 17m gives hope for a good performance at the upper bands.

Illustrative picture so far. It's not finished yet :)?
Note the double crystal filter for SSB/wide CW and narrow CW at the bottom.



73, Alex
PA1FOX