Yeah, Justin,
I'll have a go one day when I can slip down to your qth and do a little test with you. My 13cm transverter is ready to go!
I am retired, so can pretty much travel down any time during the week.
Dan VK2GG
13cm to 6cm converters
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VK2XSO
Re: 13cm to 6cm converters
I think they would make an excellent linear translator between the two bands.
Have you considered just mounting it on a hill or building with a dual band dish or some other set of antennas ?
Cross polarity. V/H or R/LHCP for TX/RX ?
Maybe try them off the shelf first before modifying the LO in them.
There's lots of space in both bands that it seems to already overlap.
A pair of them working in tandem would make an excellent long distance linear link, using either band as the link and the other as the drop.
Have you considered just mounting it on a hill or building with a dual band dish or some other set of antennas ?
Cross polarity. V/H or R/LHCP for TX/RX ?
Maybe try them off the shelf first before modifying the LO in them.
There's lots of space in both bands that it seems to already overlap.
A pair of them working in tandem would make an excellent long distance linear link, using either band as the link and the other as the drop.
Re: 13cm to 6cm converters
Looks good Matt!
good luck on finding info. Does it have the lo inbuilt?
Dan
good luck on finding info. Does it have the lo inbuilt?
Dan
Re: 13cm to 6cm converters
Hi Matt,
Look closely at your "not so busy side" - therein lie all you answers!
It contains 2 DC-DC converters (at least). From what I can see from the labels on the image, it generates 10 V, 5.1 V and -2.5 V DC from the 48 V DC supply rail. If you can determine the required currents for each supply (or at least take intelligent guesses), you can do away with the need for a -48 V supply, and replace it with a lower voltage supply (e.g. 13.8 V ish) and appropriate low voltage drop regulator (for the 10 V rail), a 5 V reg and a negative voltage generator for negative bias for the FET gate supplies. Pretty standard for ex-telecoms devices - all set up for -48 nominal input volts. Once you have an idea of required current, replace the DC-DC converter supply board with separate supplies with a convenient supply voltage DC-DC supply system, scrap the old device/s and usually lower the heat dissipation needs. It is hard to read the input required voltages, but as David says in the next post, anything in the broad range should make the thing work.
There should be some hints available on the net.
For the Qualcomm synthesizer (3236 - newer version of 3216 and 3226 synths, IIRC), look up the San Diego Microwave Group pages on the web. Excel programming aids available for download.
From the view of the image of the "busy side" it is hard to tell exactly what there is, as the vertical wall hide some detail. The middle section is clearly the PLL VCO, presumably with some switches accessible from the outside (left hand side) to set the divide ratio for the Qualcomm synth chip. The 10 MHz reference frequency is presumably the small coax coming in near the centre of this section, onto the board with the Qualcomm chip. I am not sure, but am guessing the the grey square to the right of the board with the Qualcomm chip might be a VCO device, perhaps followed by an amplifier underneath the screwed down bar running vertically. The output goes to at least 2 Wilkinson dividers following one another - the second of which splits the VCO frequency to the upper and lower sections of the assembly, probably with individual amplifier devices.
From the pic, I cannot tell what is happening in the upper section. I am guessing that this will be the reciprocal of the lower circuit - RF in (2 inputs from the eBay page link posted earlier, giving some diversity), to ?combiner, to mixer, ?BPF, then amplifier (?), to output on the RHS of the image.
In the lower section, I am guessing a bandpass filter on the RHS, to a mixer (with the LO from the synth section above) mounted above the grounded section. Output to a microstrip edge-coupled filter (5.7 GHz ish), to some amplifier sections. Next round blob is an isolator, prior to a power amplifier device with output matching section, with another isolator prior to the output on the lower left hand SMA connector. Looks like the board has some microstrip components after the "PA" device & before the output isolator for at least one more amplifier stage to be potentially added - you can see the DC & bias supply and decoupling components etched on the board.
A higher resolution photo from a more vertical view would make it easier, but hopefully my interpretation might be helpful - happy to be shot down in flames! BUT it looks nice & useful!
Good luck.
Peter VK3PF
Look closely at your "not so busy side" - therein lie all you answers!
It contains 2 DC-DC converters (at least). From what I can see from the labels on the image, it generates 10 V, 5.1 V and -2.5 V DC from the 48 V DC supply rail. If you can determine the required currents for each supply (or at least take intelligent guesses), you can do away with the need for a -48 V supply, and replace it with a lower voltage supply (e.g. 13.8 V ish) and appropriate low voltage drop regulator (for the 10 V rail), a 5 V reg and a negative voltage generator for negative bias for the FET gate supplies. Pretty standard for ex-telecoms devices - all set up for -48 nominal input volts. Once you have an idea of required current, replace the DC-DC converter supply board with separate supplies with a convenient supply voltage DC-DC supply system, scrap the old device/s and usually lower the heat dissipation needs. It is hard to read the input required voltages, but as David says in the next post, anything in the broad range should make the thing work.
There should be some hints available on the net.
For the Qualcomm synthesizer (3236 - newer version of 3216 and 3226 synths, IIRC), look up the San Diego Microwave Group pages on the web. Excel programming aids available for download.
From the view of the image of the "busy side" it is hard to tell exactly what there is, as the vertical wall hide some detail. The middle section is clearly the PLL VCO, presumably with some switches accessible from the outside (left hand side) to set the divide ratio for the Qualcomm synth chip. The 10 MHz reference frequency is presumably the small coax coming in near the centre of this section, onto the board with the Qualcomm chip. I am not sure, but am guessing the the grey square to the right of the board with the Qualcomm chip might be a VCO device, perhaps followed by an amplifier underneath the screwed down bar running vertically. The output goes to at least 2 Wilkinson dividers following one another - the second of which splits the VCO frequency to the upper and lower sections of the assembly, probably with individual amplifier devices.
From the pic, I cannot tell what is happening in the upper section. I am guessing that this will be the reciprocal of the lower circuit - RF in (2 inputs from the eBay page link posted earlier, giving some diversity), to ?combiner, to mixer, ?BPF, then amplifier (?), to output on the RHS of the image.
In the lower section, I am guessing a bandpass filter on the RHS, to a mixer (with the LO from the synth section above) mounted above the grounded section. Output to a microstrip edge-coupled filter (5.7 GHz ish), to some amplifier sections. Next round blob is an isolator, prior to a power amplifier device with output matching section, with another isolator prior to the output on the lower left hand SMA connector. Looks like the board has some microstrip components after the "PA" device & before the output isolator for at least one more amplifier stage to be potentially added - you can see the DC & bias supply and decoupling components etched on the board.
A higher resolution photo from a more vertical view would make it easier, but hopefully my interpretation might be helpful - happy to be shot down in flames! BUT it looks nice & useful!
Good luck.
Peter VK3PF
Last edited by VK3PF on Wed Nov 11, 2009 11:22 pm, edited 2 times in total.
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VK3HZ
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Re: 13cm to 6cm converters
Hi Matt,
The other option is just to build a simple unregulated 48V supply - transformer, bridge and filter C. The DC-DC converters can usually handle a wide range of input voltage.
I can't quite read the photo, but it seems the input voltage range and power capability are printed on the DC-DC converters. Pick a transformer voltage such that the peak DC (AC x 1.4 ) won't exceed the upper input voltage limit. Under load, the voltage should still be well within the converter ratings. The power capability of the converters will give you an idea of the transformer VA rating.
Regards,
Dave.
The other option is just to build a simple unregulated 48V supply - transformer, bridge and filter C. The DC-DC converters can usually handle a wide range of input voltage.
I can't quite read the photo, but it seems the input voltage range and power capability are printed on the DC-DC converters. Pick a transformer voltage such that the peak DC (AC x 1.4 ) won't exceed the upper input voltage limit. Under load, the voltage should still be well within the converter ratings. The power capability of the converters will give you an idea of the transformer VA rating.
Regards,
Dave.
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VK2TDN
Re: 13cm to 6cm converters
VK2DAG wrote:The auction is still on. It's got 1 day left and it's sitting at $49.
http://cgi.ebay.com/Microsource-ISM-ban ... 5638d2550d
Matt.
Yeah I missed out on that one they outbid me by only$10
pain in the butt when the auction ends in thewee hours of the morning dang it!!
when ya get a spare one Matt I will buy it off ya
thankyDave
VK2TDN
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VK2TDN
Re: 13cm to 6cm converters
yup have done, so will see what his response isVK2DAG wrote:Ask him if he has any more and to do a "Buy it now" for you. Set a real price like $100. If not my other one will be here soon.
Matt.
BTW Jack said the 10gig tests went well at his place on Sunday great to hear and you have finally had an
onair contact well done !!
Dave
VK2TDN