"New" Radio Arrives Tuesday

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mbott

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Doesn't that depend on the tuning step settng (the TS button on the R75)?

Yea, I'd forgotten just how easy it is to change the TS on the R75. My bad, there.

NR is only available with the DSP module installed. I have it; it works OK, but too high a setting distorts the audio.

Same.

That's where I find the tuning dial most effective.

Sometimes even that doesn't seem like an option. :(

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bob550

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GB46, the plan is to do some side by side comparisons. I do know it does have an internal power supply, but does have the capability to run from a 12v power supply too. Until I get it in front of me, details are only what I've read.

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Mike

The DC Molex connector is buried inside the back of the radio, unless it came equipped with the CK-70 kit, in which case the connector is visible on the rear. It is highly recommended to always run this rig off DC, as it will operate much cooler than on AC. Your R71 will thank you for it! I've run mine using a small 3 amp switching power supply, and had enough power left over to also run my Timewave DSP. I have since upgraded to a 19 V power supply. I can run the receiver for hours with the temp barely rising above room temperature.
 

GB46

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It is highly recommended to always run this rig off DC, as it will operate much cooler than on AC. Your R71 will thank you for it! I've run mine using a small 3 amp switching power supply, and had enough power left over to also run my Timewave DSP. I have since upgraded to a 19 V power supply. I can run the receiver for hours with the temp barely rising above room temperature.
Didn't your switching power supply emit a lot of noise? I run my R75 using a 4 amp linear regulated supply (non-switching). It sure has made a difference from the switching supply originally shipped with the receiver, which interfered not only with the R75 itself, but with my Sony portable, as well!
 

mbott

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Didn't your switching power supply emit a lot of noise? I run my R75 using a 4 amp linear regulated supply (non-switching). It sure has made a difference from the switching supply originally shipped with the receiver, which interfered not only with the R75 itself, but with my Sony portable, as well!

I was quick to point the finger at the R75s wall wart, too. But, I took the radio and the wall wart back to Universal to demonstrate the noise issue and it was quieter than a church mouse there. Not one speck of generated noise. All I can say is that it must be a combination of the wall wart and some, common wiring issue that combined to generate the noise I had at home.

I ran a Astron 4 amp also for the R75, the Cross Country Wireless multicoupler and my Timewave ANC-4. Now the Timewave and the multicoupler remain with plenty of excess should I dig out the RS DSP-40 for one of the radios.

Edited to add: The R75 sold this morning, less than 24 hours after posting in the Yahoo! R75 group. Woohoo!

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bob550

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Didn't your switching power supply emit a lot of noise? I run my R75 using a 4 amp linear regulated supply (non-switching). It sure has made a difference from the switching supply originally shipped with the receiver, which interfered not only with the R75 itself, but with my Sony portable, as well!

I thought I'd read that the R75 power supplies are more prone to causing RFI anyway. But yes, in general, switching power supplies can cause RFI whereas linear will not. But, I've not had any issues on either my R71 or SDRPlay RSP2 that I could attribute to the power supply.
 

GB46

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I was quick to point the finger at the R75s wall wart, too. But, I took the radio and the wall wart back to Universal to demonstrate the noise issue and it was quieter than a church mouse there.
I don't have the luxury of bringing radio gear back to the dealer in person, as my only Canadian source is radioworld.ca, which is in Ontario. If they offered to pay my round-trip airfare, well, that would be different. :)

I ran a Astron 4 amp also for the R75, the Cross Country Wireless multicoupler and my Timewave ANC-4. Now the Timewave and the multicoupler remain with plenty of excess should I dig out the RS DSP-40 for one of the radios.
My supply is branded "Pyramid", but maybe it's actually the same product.

The R75 sold this morning, less than 24 hours after posting in the Yahoo! R75 group. Woohoo!
Then maybe you no longer need a bigger desk. I'd never part with my R75. I guess after being discontinued, R75s can sell for a pretty high price, depending on their operating condition, which is usually good, unless they've been extensively monkeyed with. A review on eham.net indicates that the R75 is "in production". They ought to change that by now!
 

GB46

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I thought I'd read that the R75 power supplies are more prone to causing RFI anyway. But yes, in general, switching power supplies can cause RFI whereas linear will not. But, I've not had any issues on either my R71 or SDRPlay RSP2 that I could attribute to the power supply.
The battery charger for my laptop is a switching type, too. It produces only a small amount of noise, but eventually the output cord broke right at the plug, making the plug unusable. I was unable to find another plug that would fit, so I bought a 3rd-party replacement adapter designed for that laptop. The replacement was noisy as hell, so it had to be unplugged during listening sessions, and then it quit supplying power altogether, for some unknown reason. You can't service one of those things, because they're sealed, and there's probably nothing I could fix, anyway. Then I remembered that I still had the original adapter with its output cord and no plug, so I spliced the cord from the replacement to the end of the original cord, and voila, my old adapter was now back in service. It's a lot quieter, possibly because I gained an extra ferrite bead in the process.

Anyway, those switching adapters are horrible, but very widespread these days, especially because so many devices run on rechargeable batteries: cameras, cellphones, etc., and there are quite a few other AC-only devices that have no internal power supply. The smoke detector in my apartment has no batteries; it's permanently wired to the AC line, so I imagine it runs off an adapter hidden somewhere behind the apartment wall. When power is restored after an outage, the smoke detector chirps briefly.
 

bob550

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Honestly, aside from the 19 amp switching power supply I mentioned earlier, I couldn't tell you how many switching-type wall wart's I have in my shack powering everything from scanners to modems to monitors.
 

mbott

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Related story. So with the arrival of the "new to me" IC-R71A, I had a radio that was too good to sit on a shelf. So I decided to offer it up. To test the waters, I posted a for sale notice in the Yahoo! R75 board Wednesday morning. I really did not expect to sell in this group because most everyone already has a R75. Yahoo! took about 7 hours to process the message through.

Yesterday morning got an e-mail for an interested buyer. Within 2 hours, it was sold. Within 4 hours it was shipped. Woohoo! Celebrated by ordering a Palstar SP30B from Gigaparts. That arrives Monday. :)

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ridgescan

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Related story. So with the arrival of the "new to me" IC-R71A, I had a radio that was too good to sit on a shelf. So I decided to offer it up. To test the waters, I posted a for sale notice in the Yahoo! R75 board Wednesday morning. I really did not expect to sell in this group because most everyone already has a R75. Yahoo! took about 7 hours to process the message through.

Yesterday morning got an e-mail for an interested buyer. Within 2 hours, it was sold. Within 4 hours it was shipped. Woohoo! Celebrated by ordering a Palstar SP30B from Gigaparts. That arrives Monday. :)

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Mike
Toys toys toys:) Looks like you're having as much fun as me!
 

mbott

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Toys toys toys:) Looks like you're having as much fun as me!

Oh hell yes. What I failed to mention about selling the R75, is that it is on its way to Norway. Geir Laastad, LA6LU purchased it. I shipped it to a forwarder in NJ who will get it to Geir in Telemark, Norway. How cool is that!

As I said, much too nice of the radio to end up on a shelf in my LP.

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Mike
 
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