We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissible in your locale.

Author Topic: Vintage analogue/ tube receivers for BCL/SWL DXing?  (Read 4557 times)

Offline alpard

  • Sr. Member
  • ****
  • Posts: 267
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #15 on: August 11, 2020, 1400 UTC »
I picked up a Yaesu FRG-7700 for $160 years ago and wouldn't part with it for 3x that amount, Wonderful  circa 1978-1982 SWL receiver.

What do you find the 7700 good and special  compared to the other HF radios? Thanks.
ICOM R71E, Lowe HF-225, YAESU FRG100, TECSUN PL-330, PL-320, XHDATA D-109, D-808, MSi001 SDR, AOR AR3030, Sangean ATS803, ATS-909X, Antenna= Random Wire+ATU, Active Miniwhip

https://twitter.com/RadioPax88
https://www.youtube.com/@RadioPax88/videos

Offline East Troy Don

  • DX Legend
  • ******
  • Posts: 1371
  • "If you can't convince them, confuse them" Truman
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #16 on: August 11, 2020, 1531 UTC »
Sensitivity, calibration and separation are all spot on.    Using the same antenna (the Alpha Delta Sloper) thru a splitter, the FRG frequently picks up  SWL  AM signals  some of my other receivers do not.  Audio quality is very good (a front facing speaker is always better).  My only complaint(and it is minor) is that it drifts slightly on SSB.   I got mine on EBAY for only $160 because , I suppose, it didn't have the optional memory card.  I checked EBAY this morning and there are only 2 today, both rather high-priced.   But keep checking - they surface on EBAY on and off all the time. 
Primary: Yaesu FRG-7700  Secondary: ICOM R75 Tertiary: Grundig  750. Tecsun PL-990X, Tecsun PL-880 . Malahit DSP SDR V3,  Alpha Delta  SWL Sloper antenna. : Also, 1940 Mantola am/sw tube. CountyComm GP-5/SSB hand held, Tecsun PL-380 ,et al.  QTH: EAST TROY WI  USA.  Sea Level: + 320 meters .  75 miles (but not far enough) NNW of Chicago

Offline alpard

  • Sr. Member
  • ****
  • Posts: 267
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #17 on: August 11, 2020, 1607 UTC »
One of the eham reviews on the 7700 was negative on the radio. So I stayed away from it for a while.

"Not much chop   Time Owned: 3 to 6 months.
Had one
At same time had FRG7 and kenwood r1000. Kept them two, sold the 7700.

Filters too broad, not that sensitive, overloaded with images on a big antenna.

Nothing to write home about. Is Ok if you see it at a cheap price and dont expect much. But there's better buys for your buck."


But maybe his one was a lemon?

I recall times when I was using Yaesu radios. Mine were a FRG-7 and  FRG-7000.  At the time I thought they were great. The 7000 pulled a lot of DX at the time especially, but both of them sounded rather wide and loose at times.  I did let them go, and got a few portables.  Now I got a used TECSUN S-2000. It is not a perfect radio, but seems doing better than all the portables I own and use.

Still have the Yaesu FT-101ZD. I love this radio for its fantastic SSB and CW receiver audio on the ham bands. Haven't operated it a few month now due to the ham bands still not good condition.

But FRG 7700 and FRG 8800, I recall  that they used to be going for high prices in used market in 1990s. I used to drool over them, but always thought too much money for what they are.

Recently also I got feeling that most of these old rigs must be developing some sort of reliability problems with the parts going bad due to age. But with very positive remarks and recommendations on them by the real users and experienced DXers like yourself, will make us to look at, and reconsider them again.
Another important questions is, could they be repaired / restored to good daily working condition again, if they stopped working one day.  Parts availability, repairability by DIY or even by the professionals .. etc  issues like these creep into the questions.
« Last Edit: August 11, 2020, 1624 UTC by alpard »
ICOM R71E, Lowe HF-225, YAESU FRG100, TECSUN PL-330, PL-320, XHDATA D-109, D-808, MSi001 SDR, AOR AR3030, Sangean ATS803, ATS-909X, Antenna= Random Wire+ATU, Active Miniwhip

https://twitter.com/RadioPax88
https://www.youtube.com/@RadioPax88/videos

Offline Token

  • Global Moderator
  • DX Legend
  • *****
  • Posts: 2118
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #18 on: August 12, 2020, 0112 UTC »
The FRG-7700 is not a bad radio.  It is not particularly good (when compared to really good radios, like the NRD 525, Drake R8, or something), but not bad.  It competes well with other receivers in the same price class and age, it was a mid cost entry / mid level desktop in the day.  I have owned several over the years, and still own the original one I bought new in 1980.

The review on eham that states low sensitivity, wide filters, and overloading is valid, but the question becomes, what was he used to?  I find it hard to believe the two he lists, the FRG-7 and the R-1000, were any better.

The FRG-7700 sensitivity, by spec, is about 0.5 uV in SSB mode in the HF range.  The Sherwood Engineering tests showed their example at about 0.2 uV, my current copy runs about 0.24 uV for 10 dB S/N in 2.7 kHz.  This is not bad, but certainly not top shelf.  Fortunately raw sensitivity is not often an issue on HF, where you tend to be noise limited, not sensitivity limited.

The FRG-7700 does have limited filters, 3 filter widths in AM (12 kHz, 6 kHz, and 2.7 kHz), one width in SSB and CW (2.7 kHz) and one width in FM (15 kHz).  This amounts to a fair selection of usable bandwidths in AM, an adequate "normal" filter in SSB, and a far too wide filter in CW.  And while you can always change the filters out for different ones, there are not multiple selections for each mode, so you still only end up with 3 in AM, one in FM, and one for both SSB and CW.  And if you put in a nice tight CW filter then it makes SSB almost unusable.  From the filter aspect the radio was pretty obviously aimed at the SWL primarily listening in AM, that wanted SSB, CW, and FM capabilities also.

As for overloading, yes, I have seen FRG-7700s do that, but typically in pretty extreme situations.  While they can overload I have not seen it as a big problem with them.  And if / when it does overload you can crank down the gain.  There is a front panel variable attenuator, and there is also a back panel local/DX switch.

The FRG-7700 is an in between tech radio, a world that really only existed for a few years.  It is an all solid state radio with a digital display, but it is not a digital radio.  Yes, it has a digital display, but the radio itself and all the frequency sources inside it are analog (unless you have the add on external memory module), using crystals, PLLs, and similar sources.  The digital display is a digital frequency counter that is used to measure and display the analog VFO frequency.

The FRG-7700 is a decent desktop that works well, if not a stellar performer.  If you compare it to top end radios it will come up short, but if you compare it to lower end desktops, like the Radio Shack DX-302, it is quite good.

T!
« Last Edit: August 12, 2020, 0114 UTC by Token »
T!
Mojave Desert, California USA

Offline alpard

  • Sr. Member
  • ****
  • Posts: 267
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #19 on: August 12, 2020, 0747 UTC »
Great detailed info about FRG7700, thank you Token.
Yes, I feel it is a good useable HF receiver for DX SWL / BCL from your  info there.

How would it compare with the more domestic looking yet popular receivers such as Panasonic RF-2200 and RF-3100?  Because I know a very serious BCL DXer who sold his other good radios to buy the RF-2200.  I was wondering if it was a good idea to sell more modern radios, and buying the ancient vintage like RF-2200? But I thought there might be something that I don't know about the RF-2200 that he knows.

Talking about the receiver over loading, is it not the case that all receivers overload at nights when the medium bands strong stations come into the right skip? They are heard all over between 2 - 5 Mhz at certain time of the nights due to them getting really strong with the night time MW skip changes in the bands?  Many radios will suffer from this regardless the size of the antennas, unless they are using the built in whips.

And if fed with a cheap active antennas, then it could happened any time of the day from my experience. But are there receivers more robust in this problems?
« Last Edit: August 12, 2020, 1055 UTC by alpard »
ICOM R71E, Lowe HF-225, YAESU FRG100, TECSUN PL-330, PL-320, XHDATA D-109, D-808, MSi001 SDR, AOR AR3030, Sangean ATS803, ATS-909X, Antenna= Random Wire+ATU, Active Miniwhip

https://twitter.com/RadioPax88
https://www.youtube.com/@RadioPax88/videos

Offline Token

  • Global Moderator
  • DX Legend
  • *****
  • Posts: 2118
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #20 on: August 12, 2020, 2255 UTC »
How would it compare with the more domestic looking yet popular receivers such as Panasonic RF-2200 and RF-3100?  Because I know a very serious BCL DXer who sold his other good radios to buy the RF-2200.  I was wondering if it was a good idea to sell more modern radios, and buying the ancient vintage like RF-2200? But I thought there might be something that I don't know about the RF-2200 that he knows.

On MW BCB the FRG-7700 is not as good as on HF.  And the RF-2200 (I still have my RF-2200 that I bought new in 1983 or so) is very good on MW BCB.  So it is quite possible the RF-2200 will beat the FRG-7700 for MW BCB, but I really think it would come down to antennas.  If I can have a nice mag loop or a full sized antenna I would prefer the 7700 to the 2200 on MW BCB, but if I am antenna limited the RF-2200 might be the better option.

On HF the 7700, with a decent antenna, should be better.

I’ve never used the RF-3100, so I can’t speak to it.

Talking about the receiver over loading, is it not the case that all receivers overload at nights when the medium bands strong stations come into the right skip? They are heard all over between 2 - 5 Mhz at certain time of the nights due to them getting really strong with the night time MW skip changes in the bands?  Many radios will suffer from this regardless the size of the antennas, unless they are using the built in whips.

And if fed with a cheap active antennas, then it could happened any time of the day from my experience. But are there receivers more robust in this problems?

While it is technically possible for any receiver to overload, it should not be the case that all receivers overload at night on the lower HF bands.  None of the receivers I regularly use have much of a problem with this, although some of the lower end vintage receivers I break out will, especially if they are single conversion receivers.  A receiver with good dynamic range and image rejection should be able to handle anything thrown at it by any passive antenna one might find.  Overloading and images should be the exception, not the rule.

Portable receivers often have issues with overload and images, but decent desktops are much less prone to this problem.

By their nature portables tend to be less robust when it comes to front end design.  They are built to primarily work with their built in, small, inefficient, whip antennas.  A portable on a good sized external antenna may indeed overload or show image often.  And such a radio on an active antenna is asking for it to happen.

T!
T!
Mojave Desert, California USA

Offline alpard

  • Sr. Member
  • ****
  • Posts: 267
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #21 on: August 13, 2020, 1009 UTC »
I have a long wire in the garden about 60 m long, and when it connected to the radios, and tune about on the tropical bands 3 - 5 Mhz, there are always a lots of MW stations breaking in all over the place.  When I switch back to MLA30, the break through is less maybe 2 or 3. It  is OK when the wire is connected to straight to the radio, but when ATU is in between, and when the signals are peaked with the ATU, the MW signals becomes very strong too.

It is also worse between 8 - 11pm at nights. After that time, it gets a little better. I am not near any of the strong MW transmitters either.

I have a vintage single conversion receiver Lafayette HA-600, and yes it overloads even during the day. So have to make sure it is not fed with the large antennas.
« Last Edit: August 13, 2020, 1012 UTC by alpard »
ICOM R71E, Lowe HF-225, YAESU FRG100, TECSUN PL-330, PL-320, XHDATA D-109, D-808, MSi001 SDR, AOR AR3030, Sangean ATS803, ATS-909X, Antenna= Random Wire+ATU, Active Miniwhip

https://twitter.com/RadioPax88
https://www.youtube.com/@RadioPax88/videos

Offline ThaDood

  • DX Legend
  • ******
  • Posts: 1209
  • Likely, not where you are.
    • View Profile
    • Extreme Part #15!
    • Email
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #22 on: August 13, 2020, 1723 UTC »
What do you have for a good Independent Earth Ground? A decent Ground cable / rod, connected to your receiver's chassis, can improve MW rejection to, even a single conversion, receiver, when DX'ing the SW bands. Especially a double and triple conversion receiver. Then, to improve Ground soil conductivity, water the area where the Ground rod is pounded into. And BTW, a good Earth Ground can also improve your receiver's sensitivity from LF to about 15Mhz.   
I was asked, yet another weird question, of how I would like to be buried, when I finally bite the big one. The answer was actually pretty easy. Face-down, like a certain historical figure in the late 1980's, (I will not mention who, but some of you will get it, and that's enough.) Why??? It would be a burial that will satisfy everyone: (1) My enemies will say that it will show me where to go. (2) On the same point, I can have my enemies kiss my butt. (3) It will temporarily give someone a place to park a bicycle. See??? A WIN / WIN for everyone.

Offline alpard

  • Sr. Member
  • ****
  • Posts: 267
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #23 on: August 13, 2020, 2119 UTC »
What do you have for a good Independent Earth Ground? A decent Ground cable / rod, connected to your receiver's chassis, can improve MW rejection to, even a single conversion, receiver, when DX'ing the SW bands. Especially a double and triple conversion receiver. Then, to improve Ground soil conductivity, water the area where the Ground rod is pounded into. And BTW, a good Earth Ground can also improve your receiver's sensitivity from LF to about 15Mhz.

I don't use any Earth Ground.  It is because my radio shack is on the upstairs of the house.  I tried using the wire connection to the water tank in the house and the water pipes for the ground of the radios. It was a disaster , because apparently the water pipes are used for the mains electricity Earth ground here. When I connected that wire from the water pipes to my radios' ground connector, it was total wipe out of the HF freq. on some of the bands including the tropical band.  The MW signals was heard everywhere, so disconnected it immediately. Since then I had not connected anywise to the Ground post of any of my radios.

Maybe it has to be a metal rod driven into the soggy ground?, and run a thick wire to the radio shack? I wasn't sure, if it would be making such an improvement on the HF reception.
« Last Edit: August 14, 2020, 0945 UTC by alpard »
ICOM R71E, Lowe HF-225, YAESU FRG100, TECSUN PL-330, PL-320, XHDATA D-109, D-808, MSi001 SDR, AOR AR3030, Sangean ATS803, ATS-909X, Antenna= Random Wire+ATU, Active Miniwhip

https://twitter.com/RadioPax88
https://www.youtube.com/@RadioPax88/videos

Offline BoomboxDX

  • Hero Member
  • *****
  • Posts: 804
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #24 on: September 01, 2020, 0240 UTC »
Great detailed info about FRG7700, thank you Token.
Yes, I feel it is a good useable HF receiver for DX SWL / BCL from your  info there.

How would it compare with the more domestic looking yet popular receivers such as Panasonic RF-2200 and RF-3100?  Because I know a very serious BCL DXer who sold his other good radios to buy the RF-2200.  I was wondering if it was a good idea to sell more modern radios, and buying the ancient vintage like RF-2200? But I thought there might be something that I don't know about the RF-2200 that he knows.

The problem with getting a Panasonic RF-2200 is they are old radios, with horrible bandswitch mechanisms that did not age well. You could get a new Tecsun that had similar MW performance and had no such issues -- besides, a Tecsun would be cheaper. I know a lot of DXers rave about RF-2200's but I think their rep is overblown. They're great -- that is, when they are working. I have a Sony IC5900W that has similar switch mechanisms and they were impossible to fix. A lot of guys who get RF2200's find they have to either dig into them and try to repair them, or send them off to have them repaired. There are other older radios that are just as good, with more dependable switches. A GE SR2, for example.
« Last Edit: September 01, 2020, 0244 UTC by BoomboxDX »
An AM radio Boombox DXer.
+ GE SRIII, PR-D5 & TRF on MW.
The usual Realistic culprits on SW (and a Panasonic).

Offline BoomboxDX

  • Hero Member
  • *****
  • Posts: 804
    • View Profile
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #25 on: September 01, 2020, 0241 UTC »
I have a long wire in the garden about 60 m long, and when it connected to the radios, and tune about on the tropical bands 3 - 5 Mhz, there are always a lots of MW stations breaking in all over the place.  When I switch back to MLA30, the break through is less maybe 2 or 3. It  is OK when the wire is connected to straight to the radio, but when ATU is in between, and when the signals are peaked with the ATU, the MW signals becomes very strong too.

It is also worse between 8 - 11pm at nights. After that time, it gets a little better. I am not near any of the strong MW transmitters either.

I have a vintage single conversion receiver Lafayette HA-600, and yes it overloads even during the day. So have to make sure it is not fed with the large antennas.

A simple antenna tuner will help reduce MW local interference and overload. I have a Realistic DX-160 that also is single conversion, and a simple antenna tuner helped reduce the overload. In my case (I live in a low signals area) it actually eliminated it.
An AM radio Boombox DXer.
+ GE SRIII, PR-D5 & TRF on MW.
The usual Realistic culprits on SW (and a Panasonic).

Offline ThaDood

  • DX Legend
  • ******
  • Posts: 1209
  • Likely, not where you are.
    • View Profile
    • Extreme Part #15!
    • Email
Re: Vintage analogue/ tube receivers for BCL/SWL DXing?
« Reply #26 on: September 01, 2020, 1810 UTC »
Another idea for a make-shift GND? Do you have a bed with a pretty solid steel bed frame? It will act as a counter poise, but how much so is anyone's guess. And rejecting MW band better? You could roll your own Passive High Pass Filter,   http://www.learningaboutelectronics.com/Articles/High-pass-filter-calculator.php#answer2    Try 820 Ohms for the resistor, and 100pF for the capacitor.  The FREQ Cutoff on that site calculator is 1.942MHz, so anything above that should pass through, while anything below that should be attenuated. If anything, it's neat to try.
I was asked, yet another weird question, of how I would like to be buried, when I finally bite the big one. The answer was actually pretty easy. Face-down, like a certain historical figure in the late 1980's, (I will not mention who, but some of you will get it, and that's enough.) Why??? It would be a burial that will satisfy everyone: (1) My enemies will say that it will show me where to go. (2) On the same point, I can have my enemies kiss my butt. (3) It will temporarily give someone a place to park a bicycle. See??? A WIN / WIN for everyone.

 

HFUnderground Mug
HFUnderground Mug
by MitchellTimeDesigns