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Recent content by DTB Radio

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    Royce 619 PLL Unit Schematic Needed

    I'll have to double-check the model #, But I DID find it in my SAMs index at the shop. I have the SAMs manual for it, I think #254. It just has no PLL module info.
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    My RF Ammeters

    Ohms law for power when current and resistance are known is Power = Current squared times Resistance. Assuming the 10-amp current is through a 50-ohm load, we then get Power = 10 * 10 * 50 = 5000 watts. Someone please correct me if I'm wrong.
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    Royce 619 PLL Unit Schematic Needed

    I have a Royce 619 base that needs PLL repair/replacement. I have the SAMs volume for the radio, but that doesn't have any schematic for the PLL unit, just pin-outs. I've been Googling, but no luck so far. Any help appreciated!
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    Could use help with microphone project

    This is quite similar to what's already been covered above, but here's what I would start with: 1. Place a 1k-ohm resistor in series with the mic unit's output to prevent possible over-loading of the output circuit. 2. from the other end of the 1k series resistor, I'd put a variable 1k ohm to...
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    Who Else Is Fed Up With "Mud Duck Radio"?

    Yes, I'm speaking of Mark Sherman, dba Fine-Tune CB Shop out of New Mexico at the moment. Yes, he's got a good-sounding radio. Yes, he's got skills. But for the love of all things decent, respectable, and even just remotely nice, I am beyond sick and tired of hearing his incessant and...
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    VCO Block Needed, Uniden UPD857 Chassis

    Thank you very much for your reply! I'm hoping to avoid a scratch-built scenario, but I have the schematic from Sams 94 so it is doable if needed. If it DOES come to having to scratch-build one, I may go for something that uses a basic NPN transistor instead of a JFET.
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    VCO Block Needed, Uniden UPD857 Chassis

    Just realized that's not wax, its some kind of epoxy or similar resin. So much for the option of melting all the wax out of it, lol...
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    VCO Block Needed, Uniden UPD857 Chassis

    I know this is an INCREDIBLY looooong shot, but I need a working VCO block for a Standard Communications model Horizon 29 CB (its the CB that was used in the truck from The Fall Guy TV series). It uses Uniden's PC-130AA PLL module which is a UPD857-based unit. The VCO is a wax-potted...
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    TinySA pocket-sized Spectrum Analyzer

    The NanoVNA is a palm-sized 2-port vector network analyzer with a huge range of abilities including computer interface. It offers smith chart, SWR, delay readout, and a host of other functions, I've used mine for antenna analysis, tuning antenna traps, checking coax cable integrity visa S12...
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    "Blast" from the past...

    Yes, CB Radio Talk I think is what it was/is called. Didn't Bozo used to be (maybe still is) a permanent fixture over there? He's got at least 4 different domains pointing to his own page now-a-days, probably more. This 4600 is definitely a typical Radioactive radio...
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    "Blast" from the past...

    RadioActive Radios... That was a shop name that generated huge controversy and arguments a decade and more ago. I used to get many of their radios through the shop with requests to fix the assorted modification issues. When they shut down years ago, their radios showed up less and less...
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    End-fed Halfwave Matching Transformer

    I got a chance last night to do a quick and dirty test using a wire length for 80 meters. I didn't get time to fine-tune, but with a modest counterpoise was seeing less than a 2 SWR in the general vicinity of the 80, 40, and 20 meter bands. SWR climbs after 20, so I may need to "tweak" the box...
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    End-fed Halfwave Matching Transformer

    I've been puttering around with end-fed half-wave antennas for 40 through 10 meters (concentrating on 40 for now), and have had trouble coming up with a good match-box design. I've tried different ideas from an array of online sources ranging from auto-transformers in various turns ratios to...
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    Uniden pc78ltd dead key adjustment?

    There is a fairly simple way to add variable power to this radio. Go to www.dtbradio.com. click on the menu button that says "DIY Circuits", then click the "Variable Power KJit" link. That circuit can be adapted to almost any radio, and would not be hard to implement in your Uniden.