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Author Topic: How to find someone to design an 80m transceiver?  (Read 18433 times)
W6EM
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Posts: 787




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« Reply #15 on: August 28, 2013, 05:39:58 PM »

Sorry, but I didn't keep the link to the BitX20 mod to 75M, but here's a good design by Steve Weber:  kd1jv.qrpradio.com/ssbrig/SSB.HTM
The PC board is only $8.00 from Far Circuits.  www.farcircuits.net
The output power is 5.2dB less than 20W, however.

Looks like the lowest cost option.

You might want to try this one, as the parts are all easily obtained and inexpensive.

It would take a great deal of time to achieve all of the tweaking that took place with any original design.  I don't think you'll find someone willing to do that just for the asking.

The BitX20 modded would require some tweaking, involving some capacitor and inductor changes, but not a lot of them.  But, the cost of the kit of parts is "up there" a ways when compared to Weber's design.  For instance, the BitX board alone, from Far, is $25.

73,

Lee
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VE3UAL
Member

Posts: 18




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« Reply #16 on: August 28, 2013, 06:27:28 PM »

Thank you, Lee

The BitX is put out by Doug Hendricks QRP Kits but is down line from the Survivor he is now pushing but which he says we won't be able to modify as we wish.

An email from Steve Weber just an hour ago saying that anything he has is also incapable of what we are trying to do.

We long ago tried to modify Dave Benson's Warbler
and haven't found anything we can do with Park's Softrock.

Yes, we we would pay someone who could do what we need.

80m 20w no phone necessary as we are only doing PSK31.
Already have the computer software for that.

Peace and love,
Bruce
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G3RZP
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Posts: 4501




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« Reply #17 on: August 29, 2013, 05:26:47 AM »

Bruce

A professional designer would be looking at probably 30 to 45 days work to do it properly, and quite likely around at least $300 a day if he was cheap. To give you an idea, before I retired in June, I charged $750 a day, plus expenses. So unless you can find a retired RF design engineer who wants to play around for fun, you're talking a sizeable amount of change.
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VE3UAL
Member

Posts: 18




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« Reply #18 on: August 29, 2013, 06:30:09 AM »

Yes, and there is no guarantee. We have already gone through four who thought they were professionals - and $6,000 in doing so. In addition, our volunteer team has put in many hundreds of hours building and trying to debug 4 prototypes. The 'breadboard' was successful but the PC board layout was unsuccessful. Not a fault of the layout although that too needed to be improved to separate RF.

Skip Teller who designed the original Warbler circuit gave us some good advice at the outset but felt that engineering would cost $60,000. We had various bids, some higher and some lower. One was for $500,000. People have all sorts of ideas.

Dave Benson tried twice to stabilize the Warbler and I think has given up. Doug Hendricks does not feel that the Survivor can be made steady enough as an exciter for our purposes. Steve Weber who did the modifications for the Survivor emailed me yesterday and removed his 80m 25w watt design from the Internet because people trying to build it ran into problems. It wouldn't work.

I can tell you a half dozen more similar stories but the bottom line is that we need to find an existing exciter that will work in being married to an amplifier. More importantly, someone who understands what is needed. We don't need to, don't want to, and don't have the time and funds to reinvent the wheel.

Peace and love,
Bruce
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WX7G
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Posts: 5987




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« Reply #19 on: August 29, 2013, 06:56:02 AM »

Over how many units do you plan to amortize the development cost? $60,000 is the realistic low end for development cost with everything done in 500-600 hours.

Unless you plan to build over 100 of these transceivers you might want to take another look at off-the-shelf units such as the Elecraft KX3 if you want it to sip DC power or one of several 100 watt transceivers in the same $1000 price range if DC power is not so dear.

And being that a PC interface is a nice-to-have, but not a necessity, the $250 MFJ-9475 would do the job with a relaxation of the RF power spec to 12 watts.
« Last Edit: August 29, 2013, 07:05:12 AM by WX7G » Logged
WB2WIK
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Posts: 20575




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« Reply #20 on: August 29, 2013, 09:59:03 AM »

Over how many units do you plan to amortize the development cost? $60,000 is the realistic low end for development cost with everything done in 500-600 hours.

Unless you plan to build over 100 of these transceivers you might want to take another look at off-the-shelf units such as the Elecraft KX3 if you want it to sip DC power or one of several 100 watt transceivers in the same $1000 price range if DC power is not so dear.

And being that a PC interface is a nice-to-have, but not a necessity, the $250 MFJ-9475 would do the job with a relaxation of the RF power spec to 12 watts.

The MFJ uses a VFO and its frequency accuracy isn't very good.  I think for their application, something crystal controlled might be better as they provide for "unskilled operators" with no real radio training.

Now, the MFJ might be modified for crystal control.  I haven't looked at its circuit in a while, but it's likely possible.  Also for a "bulk order" like dozens of units at a time, they'd likely offer a discount.
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WX7G
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Posts: 5987




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« Reply #21 on: August 29, 2013, 10:21:10 AM »

Good
Cheap
Fast

pick any two
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WA9UAA
Member

Posts: 313




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« Reply #22 on: August 29, 2013, 11:15:12 AM »

Just briefly, as most people in manufacturing would tell you, it will almost certainly be cheaper to buy something from someone else.
73,
Rob
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VE3UAL
Member

Posts: 18




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« Reply #23 on: August 29, 2013, 04:59:16 PM »

Thanks to everyone for really putting your thought to this. Our parameters are a bit flexible but our goals are admittedly unorthodox and specific. You can see our organization at www.webpal.org and our system design goals at www.webpal.org/SAFEems/

Yes, we talked to MFJ a couple of years ago. Several exchanges but couldn't get through to the very highest levels. Slightly over our price parameter and under our performance parameter.

Earlier this week examined Elecraft again - but definitely outside our price parameter.

Quite right that it will be much better to find something already being manufactured, if we can. Have carefully examined every US manufacturer, and am listed with two search organizations for China and one for India. Have tried individual in Thailand. Have tried to search other locations using Google.

Quantity. At the moment owe 20 units to those who did initial funding. A hundred have said they will take units (and multiple units) when we can deliver. Probably wouldn't be too difficult to reach a thousand initially, letting similar organizations know of the availability. We ourselves have TEAM Leaders in all 50 US states. Our goal is for each state to have several hundred in their net but this will require both missionary work and something happening in the world to get more people concerned about preparing for a catastrophe.

If we should meet our goal of 30,000 it will require crowd sourcing to raise the funds to place the initial order. Some established manufacturer might be able to coordinate all this for us if we could find a source. It is timing, timing, timing.

As far as the trio - good, cheap, fast. We are on the cheap fast side. One band, no knobs or frills, plainest of cabinets, cheap ($10) NVIS antenna, and if the right unit is out there we would like to start arranging orders tomorrow.
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WX7G
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Posts: 5987




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« Reply #24 on: August 30, 2013, 04:39:02 AM »

It looks like you already have a solution in your successful breadboarded design. The fact that the PCB layout failed is not a solid reason to abandon a working design. The board can be laid out again using a different designer and having the parts placement reviewed before layout begins and by having the layout reviewed before ordering boards. And I suggest not being cheap. If it needs a four or six layer board do not try to make it work with two layers. If the design needs two boards for separation use two boards.

For production the unit will need to get FCC type acceptance.

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WX7G
Member

Posts: 5987




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« Reply #25 on: August 30, 2013, 07:40:58 AM »

A rather simple way to obtain a crystal controlled channelized 80 meter SSB transceiver is to mate a CB SSB transceiver ($130 in single quantities) to a transverter.

Example

Receive
LP filter
A Mini-circuits ADE-1L mixer and a 23.410 MHz LO convert 3.555 MHz to 27.405 MHz (CB channel 1), CB channel 1 to 40 give frequencies of 3.555 to 3.995 MHz

Transmit
ADE-1L mixer and 23.410 MHz LO
ERA-5 amp
PA driver
PA using two inexpensive MOSFETs
LP filter
« Last Edit: August 30, 2013, 08:00:23 AM by WX7G » Logged
VE3UAL
Member

Posts: 18




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« Reply #26 on: August 30, 2013, 08:10:24 AM »

Sounds like a real possibility, Dave

One of our members has suggested the idea before.
Need to find the amplifier design
and marry the two together.

Could possibly then look for a manufacturer somewhere like China -
that is building the CB transceiver -
to make a special model for us.

Would you be willing to assist in a project like this?
If so - please send me an email.
Anything at our www.webpal.org url

Peace and love,
Bruce
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AF6WL
Member

Posts: 139




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« Reply #27 on: August 30, 2013, 08:25:16 AM »

It looks like you already have a solution in your successful breadboarded design. The fact that the PCB layout failed is not a solid reason to abandon a working design. The board can be laid out again using a different designer and having the parts placement reviewed before layout begins and by having the layout reviewed before ordering boards. And I suggest not being cheap. If it needs a four or six layer board do not try to make it work with two layers. If the design needs two boards for separation use two boards

This is a very sensible response.

Before you give up on what you have, publish the designs - schematics and layout for peer review.
That will give you feedback of how close the current design is to being viable.
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G3RZP
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Posts: 4501




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« Reply #28 on: August 30, 2013, 08:28:38 AM »

You will need FCC Type Acceptance if you're doing this commercially.
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WX7G
Member

Posts: 5987




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« Reply #29 on: August 30, 2013, 09:06:42 AM »

Bruce,

I'll email you tomorrow with some schematics. I have the PA working in SPICE using two $1 MOSFETs. IMD is on par with good amateur radio transceivers.

FCC type acceptance is required if it is sold in the U.S.A. This does not appear to be difficult to obtain.

 
« Last Edit: August 30, 2013, 09:14:04 AM by WX7G » Logged
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