Grundig 750 question

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frazpo

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Hey there,

Is the Grundig Satellite 750 a good starter as far as an overall receiver? My interests are Aero, hams and govment. Does it pretty much cover the SW spectrum? Keep in mind I am currently using an old WW2 RBM receiver so It will not take much to impress me :)

The reason I asked specifically about this radio is the price. I am open for suggestions but please keep in my mind my budget of less than $400 or so.

Thanks
 

glennradio

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I have a friend who in the last 2 months bought himself a Satellite 750. He is interested in Aero and shortwave and raves about his radio. He is very happy and I've heard the audio for the air band and fine it quite good. You can also receive SSB so reception of the HF aeronautical bands is possible throughout the shortwave spectrum. Reception of stations is good with the stock antennas but becomes much better when an external antenna is used. I would suggest that the radio is a good buy for the price and you will be very happy with it should you choose to purchase one.
Cheers
 

frazpo

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@ka3jjz Thanks, that was very informative.
I need educated on sidebands. This radio does SSB, so what about USB and LSB? Are you limited by not having LSB and USB ?
 

majoco

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USB and LSB are SSB!

Radios that say they have SSB (single sideband) usually have a broad enough filter to cover both sidebands, Upper and Lower, and it's just a matter of fine tuning to make the transmission intelligible. A proper 'communications receiver' will have a narrow filter so that it just covers either one or the other sideband with a fixed oscillator (no knob marked BFO or clarifier) which is switched to allow 'intelligability'.

Cheers - Martin ZL2MC
 

WAScanMan

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I also have a 750. It was my 2nd SW receiver (Had the S450DLX first) but my 1st SSB capable receiver. It's really great for the price! The stock antenna works really well so you don't have to hassle with setting up another antenna right away. I have mine hooked up to a 150ft longwire and grounded to a cold water pipe. The analog S-Meter is really cool, though not accurate all the time. If you get it there's quite a few good Yahoo Groups that'll help you figure out where most of the action is.
You get continuous coverage from 100KHz-30MHz (Which includes LW/MW/SW) as well as FM Broadcast and VHF air. I got a really great deal on it from Amazon and I think they got it to me in less than 24 hours. I haven't used any of the more "high end" receivers so I can't attest to how it stacks up.
 

Halfpint

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I've got both the 750 and the bigger/older `brother' 850 and while the 850 is better at some things when it comes to performance the 750 is no slouch and does just as well *and* does it in half the physical size. In fact my 850 spends probably 70% of it's time sitting, turned off, on the same shelf as my 750 which now gets the most useage. There isn't really anything `technically' wrong/bad with the 800 except for the size. But because the 750 is smaller it is also easier to grab it whenever I want to go outside and sit in the yard and listen VS the 850.

As for `price deals'... I bought both radios from Universal Radio and feel that I got a fair deal on both of them price-wise. Right now Universal Radio has the 750 priced @ $299.95 and is `throwing in?' a Grundig G6 `Aviator' radio. (The G6 also is a fairly decent, for a small portable / `carry on' SWL ETC. radio. While it definitely isn't as `hot' as the 750 it can hold it's own fairly well, especially if one doesn't have the `room' to be hauling the 750 around in one's luggage. Or just wants to sit someplace other than in one's `shack', like out on the backyard patio or some other place where even the 750 would be too big, and do some `general listening'.)

Grundig Satellit 750 Radio Receiver
 

majoco

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WAScanMan said:
The analog S-Meter is really cool, though not accurate all the time.

Please explain how you calibrated your "S" meter so that you could make this statement.

Cheers - Martin ZL2MC
 

nanZor

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I have two of them (both modified), but make no mistake, they are not of the caliber of most amateur receivers or transceivers. See the review forum for the 750 for more details. I accepted that before purchasing them.

Inside it is essentially a portable radio inside a "portatop" case. If you like stick-shift cars, you'll like riding the rf-gain a lot to avoid distortion on medium-strong ssb even with the built-in whip. While some don't mind this, others like myself have discovered is that the front-end actually holds up pretty well for a receiver in this price class, but the amount of rf-gain needed to lower medium-signal ssb distortion can be abnormally high, even for a portable. Thus, while riding the rf-gain is the usual solution, there IS a simple mod to take care of the issue that mostly occurs downstream of the front-end rf-amp.

And since I am also an avid VHF airband listener (no the 750 will not scan), I was frustrated at having to ride the rf-gain on airband - unless of course I wanted to wear out the gain pot in a week or so as there are plenty of weak-to-strong signals as the planes fly around.

Thus you'll find a love/hate review relationship for this rig all over the place. :)

The modification for AM/SSB overload is to attenuate the AM output level with a resistor coming from the Toshiba receiver chip on pin 18 to ground. Details/pics on how to do this can be seen on the Yahoo group for the 750, where I discovered it from another user - that is why I haven't posted pics here to give him due credit. It worked so well, I ended up with two of them! Essentially the mod reveals a wider dynamic range is possible.

It is an ok starter radio for sure - there is a lot of fun to be had, but you will be more intimately involved with it on an operational basis.
 
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nanZor

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How does the 750 compare to the much cheaper Tecsun PL660?.

I have both. Apples and oranges.

What the 660 lacks compared to the 750 are continuous tone controls, continuous and fixed rf-gain adjustment, THREE individual external antenna jacks (4 if you count the longwave / mw external jack), bigger ergonomics, the ability to use 10ah D-Cells for outstanding long runtime etc.

One is a small portable, and the other a "portatop". It would be unfair to put them in the same category. I had high-hopes for the 660, but consider the 750 a better receiver, even with the need to ride rf-gain at times.
 

nanZor

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Re: the S-meter (I agree with WAScanMan)

While no s-meter is truly calibrated like the Collins gear, etc of the past, the general consensus is that on the high-end, the 750's meter is about 20db too hot. That is, compared to the usual Icom/Yaesu/Kenwood gear out, what shows up as anything from about S5-S9 on these radios, reads about 10-20db over 9 on the 750 - assuming we are switching to the same external antennas.

This is what made the strong-ssb issue so frustrating at first - it wasn't REALLY 20+ over 9 signals that needed rf gain attenuation, but moderate signal levels starting at S5 or so as shown on most other hf radios.
 
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majoco

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the general consensus is that on the high-end, the 750's meter is about 20db too hot.
So is this a con by the manufacturer that the radio is 20dB more sensitive that it's competition? Surely if the maintenance manual is available, there should be a tweaker to set the "S" meter to the correct (?) values (even though it is a vague recommendation that 50uV in 50ohms = S9!). My geriatric but still good Kenwood R2000 has such adjustments and my NRD 515 definitely is within specs!
 

nanZor

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Surely if the maintenance manual is available, there should be a tweaker to set the "S" meter to the correct (?) values (even though it is a vague recommendation that 50uV in 50ohms = S9!)....

Unfortunately, no service or maintenance manual is available from Grundig as it is considered proprietary. The only thing we can go by is a generic block diagram for a sister-Tecsun, and user testing.

The s-meter is really best used as an uncalibrated relative meter. You could tweak the s-meter, but the resolution is nowhere near 6db/S-unit. I ignore it for the most part.

Many have torn their hair out thinking it was an rf-amp issue, bad agc, etc, when it is the AM/ssb output level coming from the chip that is just a little too hot. Pad that down a little bit, and the rig settles down nicely for what it is.
 
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nanZor

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But if you had the choice icon r75 or grundig 750?

Apples and oranges again. :)

If I could only have one, of course I'd take my R75. Then again, the R75 draws nearly 10-times the current than the 750 does. This is important to me as I use solar to power my toys as a secondary hobby. Instead of using four 10ah nimh rechargeable D-cells in my 750, I have to use a 55ah AGM deep-cycle to run the R75 for about the same runtime. Schlepping my 80 watt Sanyo solar panel around is not very convenient. :) The cost difference between the two, especially when you filter-up the R75 is not insignificant.

These two radios are in such different leagues, it is unfair to both to compare them against each other.
 
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Jhkayakr

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I have the 800 but I am considering the 750 as a secondary or maybe the icom if the performance difference is really worth the cost difference.
Sorry, not meaning to hijack the thread.
 
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