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On Fri, Oct 8, 2021 at 10:44 AM, Jack, W8TEE wrote:
Rex (QRPMe.com) also sells Mepads, which makes Manhattan style construction pretty easy for anyone. David Richards (AA7EE) uses them to take homebrew to an art form:
Hi Jack, I know all about the Mepads. They are terrific and I recommend them to the new builders in The Vienna Wireless Makers group for our group build of the SimpleSSB. ?I¡¯ve also just cut up pieces of copper clad for pads and that works well. ?Dave¡¯s work is beautiful to look at¡there is both art and science to doing circuit layouts. ?I¡¯ve gotten better at layout over time. ?I¡¯ve also learned that beauty in layouts doesn¡¯t always lead to better results. ?For amps you need to worry about keeping inputs away from outputs to avoid feedback and oscillation. For filters you have to think about stray capacitance. Every you have to worry about sources of noise. ?It¡¯s different from software - ¡°readability¡± of the finished product is not necessarily a major design best practice. ?Ugly construction is as it¡¯s name applies, but works very well and after you get used to it is very quick to build. 73, Dean
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Good afternoon Farhan He uses the RD16HHF1 up to 70MHz but then changes to RD15HVF1 on 144MHz to? 432MHz
TX Output transistor -?RD16HHF1
 ?TX Output transistor -?RD16HHF1
?TX Output transistor -?RD15HVF1
?TX Output transistor -?RD15HVF1
It would push up the cost of the mbitx?if they?were used and could use the same 12V supply for more output. but it would be less likely to blow the finals Regards Lawrence
On Fri, Oct 8, 2021 at 5:14 PM Ashhar Farhan < farhanbox@...> wrote: He uses RD15HVF1 in the transverters as Sarmaji had recommended.?
On Fri, Oct 8, 2021, 8:40 PM Lawrence Galea < 9h1avlaw@...> wrote: I have two transverters and they both use the RD16HHF1. I have worked barefoot with them on both 50 and 70 MHz and I believe that he uses the same RD16HHF1 on the 144 MHz one
I built an amp almost identical to this one. I used the RD16HFF1 mosfets. It gave between 16 and 20W output from 80m to 10m, and 6W output on 6m. During sporadic E I worked several thousand km on SSB with the 6 watts, and it should be sufficient for a larger amplifier.? Here in the UK was also have &0 MHz (4 metres) but I didn't try these mosfets on that band.
Tony, G4CIZ
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The ubitx does have the rd15hfv1 footprints.
On Sat, Oct 9, 2021, 4:34 PM Lawrence Galea < 9h1avlaw@...> wrote: Good afternoon Farhan He uses the RD16HHF1 up to 70MHz but then changes to RD15HVF1 on 144MHz to? 432MHz
TX Output transistor -?RD16HHF1
?TX Output transistor -?RD16HHF1
?TX Output transistor -?RD15HVF1
?TX Output transistor -?RD15HVF1
It would push up the cost of the mbitx?if they?were used and could use the same 12V supply for more output. but it would be less likely to blow the finals Regards Lawrence
On Fri, Oct 8, 2021 at 5:14 PM Ashhar Farhan < farhanbox@...> wrote: He uses RD15HVF1 in the transverters as Sarmaji had recommended.?
On Fri, Oct 8, 2021, 8:40 PM Lawrence Galea < 9h1avlaw@...> wrote: I have two transverters and they both use the RD16HHF1. I have worked barefoot with them on both 50 and 70 MHz and I believe that he uses the same RD16HHF1 on the 144 MHz one
I built an amp almost identical to this one. I used the RD16HFF1 mosfets. It gave between 16 and 20W output from 80m to 10m, and 6W output on 6m. During sporadic E I worked several thousand km on SSB with the 6 watts, and it should be sufficient for a larger amplifier.? Here in the UK was also have &0 MHz (4 metres) but I didn't try these mosfets on that band.
Tony, G4CIZ
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I know.
What I meant if the RDs are factory installed
On Sat, Oct 9, 2021 at 3:27 PM Ashhar Farhan < farhanbox@...> wrote: The ubitx does have the rd15hfv1 footprints.
On Sat, Oct 9, 2021, 4:34 PM Lawrence Galea < 9h1avlaw@...> wrote: Good afternoon Farhan He uses the RD16HHF1 up to 70MHz but then changes to RD15HVF1 on 144MHz to? 432MHz
TX Output transistor -?RD16HHF1
?TX Output transistor -?RD16HHF1
?TX Output transistor -?RD15HVF1
?TX Output transistor -?RD15HVF1
It would push up the cost of the mbitx?if they?were used and could use the same 12V supply for more output. but it would be less likely to blow the finals Regards Lawrence
On Fri, Oct 8, 2021 at 5:14 PM Ashhar Farhan < farhanbox@...> wrote: He uses RD15HVF1 in the transverters as Sarmaji had recommended.?
On Fri, Oct 8, 2021, 8:40 PM Lawrence Galea < 9h1avlaw@...> wrote: I have two transverters and they both use the RD16HHF1. I have worked barefoot with them on both 50 and 70 MHz and I believe that he uses the same RD16HHF1 on the 144 MHz one
I built an amp almost identical to this one. I used the RD16HFF1 mosfets. It gave between 16 and 20W output from 80m to 10m, and 6W output on 6m. During sporadic E I worked several thousand km on SSB with the 6 watts, and it should be sufficient for a larger amplifier.? Here in the UK was also have &0 MHz (4 metres) but I didn't try these mosfets on that band.
Tony, G4CIZ
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I breadboard with those ¡°mepads¡± all the time. ?
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On Oct 8, 2021, at 9:45 AM, Jack, W8TEE via groups.io <jjpurdum@...> wrote:
?
Dean:
Rex (QRPMe.com) also sells Mepads, which makes Manhattan style construction pretty easy for anyone. David Richards (AA7EE) uses them to take homebrew to an art form:
 Look closely and you'll see Hans LPF in the picture. He has more pictures on his website. Everytime I visit there, I want to throw rocks at my stuff!
Jack, W8TEE
On Friday, October 8, 2021, 09:51:22 AM EDT, Dean Souleles <dsouleles@...> wrote:
On Wed, Oct 6, 2021 at 08:31 PM, Tom, wb6b wrote:
Manhattan style, seems a perfect match for these cheap CNC routers
Yes, indeed.? Here are a few more boards I cut on the CNC.? And once the design is done it's a snap to knock out another one. Dean  
-- Jack, W8TEE
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¡_. _._
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Thats where the RD15HVF1 becomes useful and about the same cost.?
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On Oct 6, 2021, at 11:59 PM, John Cunliffe W7ZQ <n2nep@...> wrote:
?The RD16HHF-1 works fine on 6m it will also work higher , I have used them all the way to 222. Both the VHF and the HF transistor are essential the same transistor only sorted for a certain gain at the upper frequency limit. Those that don't make the gain are branded for HF, Those that make the gain are branded for VHF/UHF. I have used RD16HHF-1 on 6m and 2m but they fall off above that, some do 220 within specs some not, none does 432 within specs.My 6m ,2m, and 222 transverters? all use the HF branded transistor without a problem, although I had to try several of them on 222 before I found one that worked at full gain.
John
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20 watts clean!?
I put the transmit amplifier chain together yesterday - two 2N2219A stages followed by an IRF-510 stage to get the drive level where I needed it for the dual RD16HHF1s.? After adjusting the RF gain stage I am getting 20 watts clean out - which is a bit more than I expected.? The input drive level range seems to be fairly narrow and the amp runs a bit warm. Skelton has the bias on the RD16s at 500mA.? I may try reducing the bias and see how things shake out.
?
?
73,
Dean
KK4DAS
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On Wednesday, October 20, 2021, 09:44:48 AM EDT, Dean Souleles <dsouleles@...> wrote:
20 watts clean!?
I put the transmit amplifier chain together yesterday - two 2N2219A stages followed by an IRF-510 stage to get the drive level where I needed it for the dual RD16HHF1s.? After adjusting the RF gain stage I am getting 20 watts clean out - which is a bit more than I expected.? The input drive level range seems to be fairly narrow and the amp runs a bit warm. Skelton has the bias on the RD16s at 500mA.? I may try reducing the bias and see how things shake out.
?
?
73,
Dean
KK4DAS
-- Jack, W8TEE
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Well done! ?So the input to your 2n2219a is your homebrew? Did you have to lower the output of the 510 at that point? Or is the input to your lovely amp starting someplace else?
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Hi Don ,
Yes the stage will be a new stage after the IRF 510 in the homebrew rig.? This test was just to make sure that the transmit chain was working properly. I injected a signal into the RF amp (TX pre driver) and from there it goes to the 2N2219 driver stage, and then the IRF 510, and then on to the new final.
?
I'm still tweaking the drive level and will finalize it when I integrate it with the full rig. On the bench I alternated between adjusting the drive level from the signal generator and the RF amplifier gain. The RD16 needs more drive than the 2N2219 stages could provide which is why I put the IRF510 back in the circuit.? ?I? backed off on the drive level until the IRF 510 stage was putting out about two watts.
Dean
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MadRadioModder
