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7030+ front end
For the last couple of weeks I've been testing out a 7030+. It's a very
nice receiver, all decked out with Collins filters. Until earlier today, I hadn't used it to listen to anything in the 2-3mhz range. But, largely because of an earlier thread relating to intermod and the 7030+'s front end, I decided to put it through its paces. To my surprise, there were noticeable images of big broadcast stations popping up on numerous frequencies. Now mind you, I'm in Brooklyn, NY and the BCB stations around NYC have to strain even the sturdiest front end. So, I wasn't all *that* surprised to find these images. However, it's interesting to note that none of these images are present on the Drake R8B. I don't mean this as a criticism of the 7030+, since it's a great performer with lots of interesting features. I just find this result a little surprising. Fortunately, once I put a Kiwa BCB rejection filter in line, the problem disappeared. Steve |
That's very strange indeed, as the 7030+ has the highest blocking specs of
any hobby receiver and higher than some very expensive professional receivers. It should definitely outperform a R8B in blocking out of band high power TX signals, so I suspect there is something wrong with it. Maybe whoever installed the Collins filters did not do a proper job and this is causing the breakthrough's and intermods? Don't give up on the 7030+ as over time it has proved to be one of the best RX's available. Many of the top DXer's in Europe use it and they are near 1000 KW TX's - they have no problems. Have it checked out by a professional with the workshop manual. -- John Plimmer, Montagu, Western Cape Province, South Africa South 33 d 47 m 32 s, East 20 d 07 m 32 s Icom IC-756 PRO III with MW mods RX Drake R8B, SW8 & ERGO software Sony 7600D GE SRIII BW XCR 30, Braun T1000, Sangean 818 & 803A. Hallicrafters SX-100, Eddystone 940 GE circa 50's radiogram Antenna's RF Systems DX 1 Pro, Datong AD-270 Kiwa MW Loop http://www.dxing.info/about/dxers/plimmer.dx wrote in message oups.com... For the last couple of weeks I've been testing out a 7030+. It's a very nice receiver, all decked out with Collins filters. Until earlier today, I hadn't used it to listen to anything in the 2-3mhz range. But, largely because of an earlier thread relating to intermod and the 7030+'s front end, I decided to put it through its paces. To my surprise, there were noticeable images of big broadcast stations popping up on numerous frequencies. Now mind you, I'm in Brooklyn, NY and the BCB stations around NYC have to strain even the sturdiest front end. So, I wasn't all *that* surprised to find these images. However, it's interesting to note that none of these images are present on the Drake R8B. I don't mean this as a criticism of the 7030+, since it's a great performer with lots of interesting features. I just find this result a little surprising. Fortunately, once I put a Kiwa BCB rejection filter in line, the problem disappeared. Steve |
These are probably not images reflected by the intermediate frequency but
second and/or third harmonics of the MW stations. Presumably you have ruled out any cause external to the radio, e.g., the comparison is being made using the same antenna and with no other device (including the other receiver) connected at the same time. Tom |
Yes, only a single antenna is being used. I now think something has to
be wrong with the 7030+ because the overload I'm experiencing on it is actually worse than the overload I experience on my Lowe HF-150--so, that clinches it. My guess is the SD5400 mixer needs to be replaced, but that's just a guess. No other aspect of the receiver's functioning appears compromised. It's as sensitive as ever and an external highpass filter temporarily improves things. I can send it off to AOR UK if necessary, though it'll have to wait a few weeks until my business travel has ended. If any of you guys have other hypotheses about what the source of this difficulty is, please let me know. Thanks. Steve |
http://www.aoruk.com/pdf/fet.pdf
The above link should shed some light on your situation..........it looks as if the SD5400 mixer is damaged. It shouldn't be too hard to replace. I don't have any of those on hand, or I would send you one of them. Pete wrote in message ups.com... Yes, only a single antenna is being used. I now think something has to be wrong with the 7030+ because the overload I'm experiencing on it is actually worse than the overload I experience on my Lowe HF-150--so, that clinches it. My guess is the SD5400 mixer needs to be replaced, but that's just a guess. No other aspect of the receiver's functioning appears compromised. It's as sensitive as ever and an external highpass filter temporarily improves things. I can send it off to AOR UK if necessary, though it'll have to wait a few weeks until my business travel has ended. If any of you guys have other hypotheses about what the source of this difficulty is, please let me know. Thanks. Steve |
http://www.aoruk.com/7030bulletin.htm
This link has all of the service bulletins for the 7030. Pete wrote in message ups.com... Yes, only a single antenna is being used. I now think something has to be wrong with the 7030+ because the overload I'm experiencing on it is actually worse than the overload I experience on my Lowe HF-150--so, that clinches it. My guess is the SD5400 mixer needs to be replaced, but that's just a guess. No other aspect of the receiver's functioning appears compromised. It's as sensitive as ever and an external highpass filter temporarily improves things. I can send it off to AOR UK if necessary, though it'll have to wait a few weeks until my business travel has ended. If any of you guys have other hypotheses about what the source of this difficulty is, please let me know. Thanks. Steve |
If you check the front end configuration of these two receivers, you'll see
that the Drake R-8 has a half octave switched preselector filter, and the AOR7030 has only a low pass filter. That will make a big difference in what shows up near the broadcast band. When you put the BCB blocking filter in front of the 7030 that's equivalent to what is already in the Drake. I expect the 7030 is working up to specs. John Reed "John Plimmer" wrote in message ... That's very strange indeed, as the 7030+ has the highest blocking specs of any hobby receiver and higher than some very expensive professional receivers. It should definitely outperform a R8B in blocking out of band high power TX signals, so I suspect there is something wrong with it. Maybe whoever installed the Collins filters did not do a proper job and this is causing the breakthrough's and intermods? Don't give up on the 7030+ as over time it has proved to be one of the best RX's available. Many of the top DXer's in Europe use it and they are near 1000 KW TX's - they have no problems. Have it checked out by a professional with the workshop manual. -- John Plimmer, Montagu, Western Cape Province, South Africa South 33 d 47 m 32 s, East 20 d 07 m 32 s Icom IC-756 PRO III with MW mods RX Drake R8B, SW8 & ERGO software Sony 7600D GE SRIII BW XCR 30, Braun T1000, Sangean 818 & 803A. Hallicrafters SX-100, Eddystone 940 GE circa 50's radiogram Antenna's RF Systems DX 1 Pro, Datong AD-270 Kiwa MW Loop http://www.dxing.info/about/dxers/plimmer.dx wrote in message oups.com... For the last couple of weeks I've been testing out a 7030+. It's a very nice receiver, all decked out with Collins filters. Until earlier today, I hadn't used it to listen to anything in the 2-3mhz range. But, largely because of an earlier thread relating to intermod and the 7030+'s front end, I decided to put it through its paces. To my surprise, there were noticeable images of big broadcast stations popping up on numerous frequencies. Now mind you, I'm in Brooklyn, NY and the BCB stations around NYC have to strain even the sturdiest front end. So, I wasn't all *that* surprised to find these images. However, it's interesting to note that none of these images are present on the Drake R8B. I don't mean this as a criticism of the 7030+, since it's a great performer with lots of interesting features. I just find this result a little surprising. Fortunately, once I put a Kiwa BCB rejection filter in line, the problem disappeared. Steve |
I'd be tempted to agree with you if I hadn't compared the 7030+ with my
HF-150 this morning. The HF-150 was significantly less prone to overload than the 7030+, and I can't believe it would be if the latter were performing up to specs. I suspect the SD5400 mixer is damaged, since that's known to produce this sort of problem. I'm also sort of hoping it's a damaged SD5400 mixer, since that's a relatively easy thing to fix. Steve |
"John Plimmer" wrote (in part):
snip That's very strange indeed, as the 7030+ has the highest blocking specs of any hobby receiver and higher than some very expensive professional receivers. snip I had the good fortune to have a 7030+ to play with for a couple of weeks. I would sell kidney or other spare body part tonight to buy one. However I live less then 4 miles from a littlel 1KW MW on 770. And we a few fairly local power houses at 590 and 630 and 1300. On the 7030+ I could receive the 770+590 fairly strong the , the 770+630 and and the 770+1300 very strong. In a nearby park about twice as far from the 770 station as my home, I get no mix products. The 770 is so strong that it will show up in most receivers even with the antenna disconnected and replaced with a 50 ohm terminator. By most receivers I mean R390, R392, R5000, R2000 DX389(3.5mm plug inserted), the 7030+ and every automotive radio I have ever tested. I suspect that the 770KHz is so strong is just causes the front end to "colapse". It is funny that my PRC1000 requires at least a paper clip to receive it. I can receive them on a simple crustal set with just the leads to the earphones. I am very glad they are only 1KW and daytime only! Terry |
"John Plimmer" wrote (in part): I would sell kidney or other spare body part tonight to buy one. However I live less then 4 miles from a littlel 1KW MW on 770. And we a few fairly local power houses at 590 and 630 and 1300. On the 7030+ I could receive the 770+590 fairly strong the , the 770+630 and and the 770+1300 very strong. In a nearby park about twice as far from the 770 station as my home, I get no mix products. The 770 is so strong that it will show up in most receivers even with the antenna disconnected and replaced with a 50 ohm terminator. Is there any possibility that you have the rear-panel pre-amp turned on in the 7030? What happens when you add in 10 dB or so of attenuation? Rick Kunath |
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Rick Kunath wrote: "John Plimmer" wrote (in part): I would sell kidney or other spare body part tonight to buy one. However I live less then 4 miles from a littlel 1KW MW on 770. And we a few fairly local power houses at 590 and 630 and 1300. On the 7030+ I could receive the 770+590 fairly strong the , the 770+630 and and the 770+1300 very strong. In a nearby park about twice as far from the 770 station as my home, I get no mix products. The 770 is so strong that it will show up in most receivers even with the antenna disconnected and replaced with a 50 ohm terminator. Is there any possibility that you have the rear-panel pre-amp turned on in the 7030? What happens when you add in 10 dB or so of attenuation? Rick Kunath I tried adding 10 db attenuation and even more, but it didn't help. Steve |
Telamon wrote:
The 7030 has a metal case and so is shielded. This looks like a good case of the BCB station coming in on the power cord through the house wiring. With the 50 ohm resistor on the antenna terminal use a RF choke on the DC power cord to the radio to see if the AM station goes away. Same should work for any other radio that has a metal case. The non-shielded radios may have the RF go through the case as an additional path to consider. -- Telamon Ventura, California -------------------------------------------- I can only wish I had my own 2030+. This was a borrowed unit from a friend who was wrapping up the sale of her family farm after graduation. I did try to place several ferrite RFI "snap on", and while I could reduce the interference, even with over 10 on the power cord I still had a very weak signal on 770 and the 770+590. I was really suprised by the R390 and R392. In these receivers the RF was getting in through the audio line. High level RF is hard to completly supress. At least the 770 station cleaned up their harmonics. A nice letter with the comment that I would hate for them to get fined for improper operation got the problem solved within a week. The 1540, 2310 and 3850 were very strong. No 4rth harmonic at all. A high pass filter ruled out my receivers. I wonder how many people have MW ingress and don't know it. Sometime "real soon" I am going to psot the results of my RF week end and how bad normal single or double brain only coax is. By bad, I mean allows LW/MW and HF if any stations are close or strong enough to leak in even with out an antenna connected. I tested 100' of various good quality (Belden) coax. and one run of 200' (borrowed) run of triax. Terry Terry |
I considered this, but I think the problem is too severe...especially
since the HF-150, with its notiously weak front end, is not as badly affected. Also, tonight I noticed an image not just of a powerhouse broadcast station here in NYC, but of a relatively strong shortwave signal (Radio China International). I think a little bench time is required to correct this problem. Steve |
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Rick Kunath wrote:
Is there any possibility that you have the rear-panel pre-amp turned on in the 7030? What happens when you add in 10 dB or so of attenuation? Rick Kunath ------------------------------------------------------------------------ Preamp was off. Attenuation didn't mater. It was reduced with a 50 Ohm termanator on the antenna port but not eliminated. Wasn't bad enough to be a problem, after all if a R390 and the R392, completly shielded in a tough aluminium case with 4 1/4" bolts per side of the front pannel, that amke good contact witht he front panel and the case, both received the 770KHz signal, I wan't suprised the 7030+ and almost every other receiver I have tried picks it up. I would consider selling a kidney tonight, if legal, to get one. I LOVED the receiver. Sadly the ARM and QRN noise floor is my limiting factor, even my R2000s don't reach their internal noise floor because of the external crap. But the selection of filters, the synch detector, tunning steps, optional PC control make the 7030+ my dream receiver. At my QTH any signal I could receive with the 7030+ I could receive with either of R2000s. But the synch detector is magic. The better filters allow listening to weak signals that will give you a head ach on the R2000s. Signals that are dificult to impossible to understand on the R2000 are hard much easier to understand. I can't explain the difference, reminds me of the tube/valve HiFi debate, but I will never be satisfied unitl I have my own 7030+. Even with similar bandwidths the 7030+ is the clear winner. And it isn't just a pahse noise issue. Comparing it to a R390 and R392 in a friends fairly RFquite country home, the 7030+ beat the R390 and R392 in weak signal "understandability". I don't have a scale to measure it, or even words to really discribe it, but the 7030+ is just "cleaner". The R39X have "no" phase noise. I had always writtensome of the less then perfect weak signal performance of the R2000 to phase noise. I now know that isn't the whole story. Don't get me wrong, for what I have in my R2000 they are great receivers. Kind of like comparing a Toyota Camray to a Lamborghini. The Camray will get you there, but the Lamborghini will really get you there. The only improvement for the AOR 7030+ that I can think of is a 90% price reduction. I would gladly trade my PCs and all of my radios, ham gear included for a 7030+. Terry |
The 7030 has a low-pass image reject filter that cuts off just above 30MHz,
a low-pass filter that cuts off at 1.7MHz, and a high-pass filter that cuts off at 1.7MHz, so MW bleedthrough shouldn't be a problem. If there is enough interest, I will market a 7-band preselector. This will consist of a low-pass filter for the range below 500kHz, with bandpass filters for the ranges above 500kHz. I will use PIN diodes for range changing. Interested parties can e-mail me directly and we can go from there. Pete wrote in message oups.com... I'd be tempted to agree with you if I hadn't compared the 7030+ with my HF-150 this morning. The HF-150 was significantly less prone to overload than the 7030+, and I can't believe it would be if the latter were performing up to specs. I suspect the SD5400 mixer is damaged, since that's known to produce this sort of problem. I'm also sort of hoping it's a damaged SD5400 mixer, since that's a relatively easy thing to fix. Steve |
I'm using a Wellbrook 330S antenna and I don't think it's suffering
from any problems. I use it with my other receivers and they seem to function well with it. Occasionally there's overload on the HF-150, but it's always pretty minor, not like what I'm experiencing with the 7030. This makes me suspect the problem isn't with the antenna. I can even connect my SW77 to this antenna without getting the kind of overload I'm finding on the 7030. Steve |
wrote in message oups.com... I considered this, but I think the problem is too severe...especially since the HF-150, with its notiously weak front end, is not as badly affected. Also, tonight I noticed an image not just of a powerhouse broadcast station here in NYC, but of a relatively strong shortwave signal (Radio China International). I think a little bench time is required to correct this problem. Steve So Steve, does the 7030 feel a lot like the 150 since Mr.Thorpe designed both? Can you see a lot of the 150 in it? Do you think the 7030 is worth that much more then the 150? Would you call the 150 the "poor man 7030?" Lucky |
"Pete KE9OA" wrote:
The 7030 has a low-pass image reject filter that cuts off just above 30MHz, a low-pass filter that cuts off at 1.7MHz, and a high-pass filter that cuts off at 1.7MHz, so MW bleedthrough shouldn't be a problem. If there is enough interest, I will market a 7-band preselector. This will consist of a low-pass filter for the range below 500kHz, with bandpass filters for the ranges above 500kHz. I will use PIN diodes for range changing. Interested parties can e-mail me directly and we can go from there. Pete ----------------------------------------------------------------------- Sadly Google beat removes part of email addresses. Please email me at: r2000swler at hotmail dot com The preselector sounds interesting. Terry |
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Those are all good radios. I never owned the R8B, but I have played with it,
and it is a very good receiver. I do have the AOR7030 (original version), along with the HF-150 and the HF-225. All of them sound similar, and have very similar sensitivity, except that the 7030 does have better IM rejection. The HF-225 is similar in sensivity to the HF-150 with the exception that the HF-150 has better sensivity on the MW band when using the Radio Shack loop antenna. With a long wire, though, performance is very similar. The HF-150 does seem to have the best bass response of the bunch, while I would describe the sound of the 7030 as more "open and airy". I think this is because the 7030 has better treble response. I think that the slight difference in sound is also because of that Plessey SL6700 I.F. system that the Lowe receivers used, although the TDA1572 that the 7030 uses is also a very good chip. I have been using the 1572 in my own designs for several years.............measured distortion on AM is .3% @1kHz @60% modulation index. Even with the 7030's relatively open front end, I don't hear any MW IMD products on the LW band, while I do hear them on the HF-150. Still, now that I have added that Lumitex fiber optic backlight panel to my HF-150, it makes for a great bedside radio. Pete "Telamon" wrote in message ... In article .com, wrote: The case of the 7030 is very solid, like the 150's. The sparse controls on the front panel is also reminiscent of the 150, as is the solid tuning knob. Performance wise they're quite different. The 7030 is a DX machine and it feels like it. My experience with the 7030 is still pretty limited, but I'd have to say I still favor the R8B overall. I don't mind the ergonomics of the 7030, but the 7030's sync detector, although it's very good, can't quite lock onto signals as weak as the ones the R8B's can snag, and often I find that it takes a fair amount of adjusting and knob twiddling to end up with a signal that's as good as the one you get right away on the Drake. But the 7030 is great and I especially like its notch filter. I'm sure lots of people would prefer the 7030 to the R8B, depending on their preferences and listening styles. I hope we hear from John Thorpe again one of these days.... I hope so too especially now that Drake has bowed out of the market. I generally like my 7030+ it is a cool radio and has some features the Drake R8B does not have like the auto notch, auto filter calibration and a remote control but I like the Drake R8B more the way it operates and it generally seems to do a better job of making weak signals listen-able. I own three table tops RX340, Drake R8B and the 7030+ all of which I like for different reasons. They are all great radios and I'm pleased to own all of them. -- Telamon Ventura, California |
"Pete KE9OA" ) writes: That's ok........my e-mail address is: Pete No, the problem is that google is masking email addresses in the newsgroup archive. This started with the new interface that became the norm back in December. Over at google, they show it like: From: "Pete KE9OA" and in the body: my e-mail address is: I've heard that if one "joins" a group over there (an additional step beyond registering to post) you do see email addresses, but I've not tried that. I suppose the only way to get around it is to use the link for replying to the author, but I've not tried that either. Michael wrote in message ups.com... "Pete KE9OA" wrote: The 7030 has a low-pass image reject filter that cuts off just above 30MHz, a low-pass filter that cuts off at 1.7MHz, and a high-pass filter that cuts off at 1.7MHz, so MW bleedthrough shouldn't be a problem. If there is enough interest, I will market a 7-band preselector. This will consist of a low-pass filter for the range below 500kHz, with bandpass filters for the ranges above 500kHz. I will use PIN diodes for range changing. Interested parties can e-mail me directly and we can go from there. Pete ----------------------------------------------------------------------- Sadly Google beat removes part of email addresses. Please email me at: r2000swler at hotmail dot com The preselector sounds interesting. Terry |
I understand what you mean..................I go through worldnet, so I see
all of the e-mail addresses. Pete "Michael Black" wrote in message ... "Pete KE9OA" ) writes: That's ok........my e-mail address is: Pete No, the problem is that google is masking email addresses in the newsgroup archive. This started with the new interface that became the norm back in December. Over at google, they show it like: From: "Pete KE9OA" and in the body: my e-mail address is: I've heard that if one "joins" a group over there (an additional step beyond registering to post) you do see email addresses, but I've not tried that. I suppose the only way to get around it is to use the link for replying to the author, but I've not tried that either. Michael wrote in message ups.com... "Pete KE9OA" wrote: The 7030 has a low-pass image reject filter that cuts off just above 30MHz, a low-pass filter that cuts off at 1.7MHz, and a high-pass filter that cuts off at 1.7MHz, so MW bleedthrough shouldn't be a problem. If there is enough interest, I will market a 7-band preselector. This will consist of a low-pass filter for the range below 500kHz, with bandpass filters for the ranges above 500kHz. I will use PIN diodes for range changing. Interested parties can e-mail me directly and we can go from there. Pete ----------------------------------------------------------------------- Sadly Google beat removes part of email addresses. Please email me at: r2000swler at hotmail dot com The preselector sounds interesting. Terry |
I just spoke with Richard Hillier of AOR UK. He confirmed that the 7030
should not be displaying any of the overload problems I'm encountering, and he suspects that it is indeed the SD5400 mixer that's the problem. He also noted something that should interest other 7030 owners out the namely, that the SD5400 mixer is *very* static sensitive. In fact, he suspects that mine was damaged when it got zapped at some point....this is apparently the way it happens most of the time.So, whenever your plugging in external speakers, headphones or anything like that, be very careful! Steve |
wrote: I just spoke with Richard Hillier of AOR UK. He confirmed that the 7030 should not be displaying any of the overload problems I'm encountering, and he suspects that it is indeed the SD5400 mixer that's the problem. He also noted something that should interest other 7030 owners out the namely, that the SD5400 mixer is *very* static sensitive. In fact, he suspects that mine was damaged when it got zapped at some point....this is apparently the way it happens most of the time.So, whenever your plugging in external speakers, headphones or anything like that, be very careful! Sounds like that AOR stuff is as plagued by problems as the ICOM's are... dxAce Michigan USA http://www.iserv.net/~n8kdv/dxpage.htm |
dxAce wrote: wrote: I just spoke with Richard Hillier of AOR UK. He confirmed that the 7030 should not be displaying any of the overload problems I'm encountering, and he suspects that it is indeed the SD5400 mixer that's the problem. He also noted something that should interest other 7030 owners out the namely, that the SD5400 mixer is *very* static sensitive. In fact, he suspects that mine was damaged when it got zapped at some point....this is apparently the way it happens most of the time.So, whenever your plugging in external speakers, headphones or anything like that, be very careful! Sounds like that AOR stuff is as plagued by problems as the ICOM's are... dxAce Michigan USA http://www.iserv.net/~n8kdv/dxpage.htm It certainly is a design flaw, in my opinion, to have a critical component be so vulnerable to static electricity. Of course any receiver is going to have to have its weak points, but you shouldn't have to worry every time you plug in an external speaker or a set of headphones. That's just common sense. If there's ever a 7030++, maybe they'll farm some work out to the Drake designers.... Steve |
wrote: dxAce wrote: wrote: I just spoke with Richard Hillier of AOR UK. He confirmed that the 7030 should not be displaying any of the overload problems I'm encountering, and he suspects that it is indeed the SD5400 mixer that's the problem. He also noted something that should interest other 7030 owners out the namely, that the SD5400 mixer is *very* static sensitive. In fact, he suspects that mine was damaged when it got zapped at some point....this is apparently the way it happens most of the time.So, whenever your plugging in external speakers, headphones or anything like that, be very careful! Sounds like that AOR stuff is as plagued by problems as the ICOM's are... dxAce Michigan USA http://www.iserv.net/~n8kdv/dxpage.htm It certainly is a design flaw, in my opinion, to have a critical component be so vulnerable to static electricity. Of course any receiver is going to have to have its weak points, but you shouldn't have to worry every time you plug in an external speaker or a set of headphones. That's just common sense. Kind of like the Sony 2010 which seemed prone to static electricity as well. If there's ever a 7030++, maybe they'll farm some work out to the Drake designers.... Yeah, the AOR-Drake R9.... and hopefully Drake would put a 'real' S meter on it. dxAce Michigan USA |
Here's an update:
I sent the 7030+ to AOR UK. They replaced the SD5400 mixer and one of the front end supply chokes. Once inside the receiver, they also found a slightly leaky preamp transformer, so they replaced that while they were at it. The receiver is working perfectly now...no more overload. And it sounds great with the Collins filters. Steve wrote: For the last couple of weeks I've been testing out a 7030+. It's a very nice receiver, all decked out with Collins filters. Until earlier today, I hadn't used it to listen to anything in the 2-3mhz range. But, largely because of an earlier thread relating to intermod and the 7030+'s front end, I decided to put it through its paces. To my surprise, there were noticeable images of big broadcast stations popping up on numerous frequencies. Now mind you, I'm in Brooklyn, NY and the BCB stations around NYC have to strain even the sturdiest front end. So, I wasn't all *that* surprised to find these images. However, it's interesting to note that none of these images are present on the Drake R8B. I don't mean this as a criticism of the 7030+, since it's a great performer with lots of interesting features. I just find this result a little surprising. Fortunately, once I put a Kiwa BCB rejection filter in line, the problem disappeared. Steve |
In article .com,
wrote: Here's an update: I sent the 7030+ to AOR UK. They replaced the SD5400 mixer and one of the front end supply chokes. Once inside the receiver, they also found a slightly leaky preamp transformer, so they replaced that while they were at it. The receiver is working perfectly now...no more overload. And it sounds great with the Collins filters. Steve wrote: For the last couple of weeks I've been testing out a 7030+. It's a very nice receiver, all decked out with Collins filters. Until earlier today, I hadn't used it to listen to anything in the 2-3mhz range. But, largely because of an earlier thread relating to intermod and the 7030+'s front end, I decided to put it through its paces. To my surprise, there were noticeable images of big broadcast stations popping up on numerous frequencies. Now mind you, I'm in Brooklyn, NY and the BCB stations around NYC have to strain even the sturdiest front end. So, I wasn't all *that* surprised to find these images. However, it's interesting to note that none of these images are present on the Drake R8B. I don't mean this as a criticism of the 7030+, since it's a great performer with lots of interesting features. I just find this result a little surprising. Fortunately, once I put a Kiwa BCB rejection filter in line, the problem disappeared. That was quick. How was it shipped and how much did the shipping and repair cost? Mine is working well but the display is getting dim in places. The display is readable, it's a cosmetic thing. I was also thinking of getting some better filters for it. What do you recommend for program listening? -- Telamon Ventura, California |
Telamon wrote:
snip I was also thinking of getting some better filters for it. What do you recommend for program listening? For AM mode I like a filtronetics marked 6.8khz that reads 6.1 For nice fidelity Sideband, I like a filtronetics marked 3.24khz that reads 2.9 Both are crystal filters originally intended for the Racal 6790/gm. They have very steep skirts, and the radio sounds beautiful with them. |
It was shipped UPS, and AOR UK told me they prefer UPS as this
apparently simplifies things with customs. I probably would not have shipped it to them for a repair that was primarily cosmetic because the shipping is expensive. It's impossible to say exactly what it would cost you, since the cost is a function not only of the weight of the package but also of its dimensions. If you use a large box with lots and lots of styrofoam, it's going to cost you--and it might cost more coming from California. I think you should expect it to run at least a few hundred bucks, though, there and back, unless you cut corners. USPS might be a little cheaper. If you visit the UPS homepage you can calculate costs using different measurements and points of origin. I only did it because the repair was fairly serious and I really like the receiver, its custom filters, etc. It's hard for me to recommend filters for this receiver. Mine is decked out entirely with Collins filters. This wouldn't be to everyone's taste, but I like it. However, I've never listened to this receiver with any other kinds of filters, so I can't make an informed comparison. Steve Telamon wrote: That was quick. How was it shipped and how much did the shipping and repair cost? Mine is working well but the display is getting dim in places. The display is readable, it's a cosmetic thing. I was also thinking of getting some better filters for it. What do you recommend for program listening? -- Telamon Ventura, California |
In article ,
"Mark S. Holden" wrote: Telamon wrote: snip I was also thinking of getting some better filters for it. What do you recommend for program listening? For AM mode I like a filtronetics marked 6.8khz that reads 6.1 For nice fidelity Sideband, I like a filtronetics marked 3.24khz that reads 2.9 Both are crystal filters originally intended for the Racal 6790/gm. They have very steep skirts, and the radio sounds beautiful with them. Is this them? Filtronetics, Inc. 6010 Parretta Dr Kansas City, Missouri 64120 UNITED STATES Phone: 816-231-7375 (Ext. 335) Fax: 816-241-0368 They don't appear to have a web site. Do you have part numbers on the 6.8 KHz filter? Another question is what did it take to install it in the 7030+? -- Telamon Ventura, California |
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In article
, Telamon wrote: In article , "Mark S. Holden" wrote: Telamon wrote: snip I was also thinking of getting some better filters for it. What do you recommend for program listening? For AM mode I like a filtronetics marked 6.8khz that reads 6.1 For nice fidelity Sideband, I like a filtronetics marked 3.24khz that reads 2.9 Both are crystal filters originally intended for the Racal 6790/gm. They have very steep skirts, and the radio sounds beautiful with them. Is this them? Filtronetics, Inc. 6010 Parretta Dr Kansas City, Missouri 64120 UNITED STATES Phone: 816-231-7375 (Ext. 335) Fax: 816-241-0368 They don't appear to have a web site. Do you have part numbers on the 6.8 KHz filter? Another question is what did it take to install it in the 7030+? I found a web site by them http://www.filtro.net Here is a page with 455KHz centered crystal filters among others http://www.filtro.net/products/filters/filters.asp FN-860W 6 KHz/3 dB - 19 KHz/60 dB FN-169W 3 KHz/3 dB - 6.2 KHz/60 dB They don't have any 455 KHz ceramics. -- Telamon Ventura, California |
Yes, I personally wouldn't go to all that trouble and expense for
something cosmetic. Before sending mine off to AOR UK, I called Universal to see if anyone there would touch it, but no dice. They said they repair the ones they sell, but no others. And to be honest, with all due respect to Universal, I understand that repairing the 7030+ is quite tricky. The folks at AOR UK told me that, when they were selling the 7030+ in the US, the technicians at AOR USA were not very good at repairing them. I don't know why the 7030+ would be more difficult to repair than any other high-end consumer grade receiver, but that's what I was told. Steve |
Telamon wrote:
In article , "Mark S. Holden" wrote: Telamon wrote: snip I was also thinking of getting some better filters for it. What do you recommend for program listening? For AM mode I like a filtronetics marked 6.8khz that reads 6.1 For nice fidelity Sideband, I like a filtronetics marked 3.24khz that reads 2.9 Both are crystal filters originally intended for the Racal 6790/gm. They have very steep skirts, and the radio sounds beautiful with them. Is this them? Filtronetics, Inc. 6010 Parretta Dr Kansas City, Missouri 64120 UNITED STATES Phone: 816-231-7375 (Ext. 335) Fax: 816-241-0368 They don't appear to have a web site. Do you have part numbers on the 6.8 KHz filter? Another question is what did it take to install it in the 7030+? The web site is: http://www.filtro.net/ I couldn't find the ones I have on their web site, so they may have been done for a specific contract. Getting a non production bandwidth from them may or may not be a big deal. Back when I had the 6790/gm I ran into a small supply of the 3.24khz symmetrical filters, and jumped on them because I love the 3.2khz bandwidth on my Harris, and they're for a common IF frequency. When I got the 7030+ I installed one. After seeing how well it performed, I started hunting down 6790 filters suitable for AM. Along the way I found the McCoy 6khz mechanical filter for the 6790 was an impedance mismatch and wouldn't read. I'll need to open up my radio to track down the part number for the 6.8khz filter - I've got an extra layer of case to deal with as my radio is installed in an equipment case with battery packs and so forth to make it "portable". But I'll see if I can get it for you tomorrow. I used some angle aluminum and flat stock to make a shelf for the filters that sits on the inside back wall of the radio. AOR thoughtfully provided nicely spaced holes for attaching it to the back panel. I used stuff I had in stock. The filters are on their side, and are held with velcro. I used RG174 to feed the terminals into the holes you'd solder extra filters into on the main PC board. I'll try to remember to shoot some pictures while I've got it open. The reason these filters sound so good is they're a little wide with very steep skirts. (1:1.33 on the sideband one) Regards, Mark |
In article ,
"Mark S. Holden" wrote: Telamon wrote: In article , "Mark S. Holden" wrote: Telamon wrote: snip I was also thinking of getting some better filters for it. What do you recommend for program listening? For AM mode I like a filtronetics marked 6.8khz that reads 6.1 For nice fidelity Sideband, I like a filtronetics marked 3.24khz that reads 2.9 Both are crystal filters originally intended for the Racal 6790/gm. They have very steep skirts, and the radio sounds beautiful with them. Is this them? Filtronetics, Inc. 6010 Parretta Dr Kansas City, Missouri 64120 UNITED STATES Phone: 816-231-7375 (Ext. 335) Fax: 816-241-0368 They don't appear to have a web site. Do you have part numbers on the 6.8 KHz filter? Another question is what did it take to install it in the 7030+? The web site is: http://www.filtro.net/ I couldn't find the ones I have on their web site, so they may have been done for a specific contract. Getting a non production bandwidth from them may or may not be a big deal. Back when I had the 6790/gm I ran into a small supply of the 3.24khz symmetrical filters, and jumped on them because I love the 3.2khz bandwidth on my Harris, and they're for a common IF frequency. When I got the 7030+ I installed one. After seeing how well it performed, I started hunting down 6790 filters suitable for AM. Along the way I found the McCoy 6khz mechanical filter for the 6790 was an impedance mismatch and wouldn't read. I'll need to open up my radio to track down the part number for the 6.8khz filter - I've got an extra layer of case to deal with as my radio is installed in an equipment case with battery packs and so forth to make it "portable". But I'll see if I can get it for you tomorrow. I used some angle aluminum and flat stock to make a shelf for the filters that sits on the inside back wall of the radio. AOR thoughtfully provided nicely spaced holes for attaching it to the back panel. I used stuff I had in stock. The filters are on their side, and are held with velcro. I used RG174 to feed the terminals into the holes you'd solder extra filters into on the main PC board. I'll try to remember to shoot some pictures while I've got it open. The reason these filters sound so good is they're a little wide with very steep skirts. (1:1.33 on the sideband one) Yeah, I found their web site after my previous post. Usenet does not work in real time. Sometimes faster than other times. Ignore my other post where I found it. Please don't take your radio apart on my account, I'll figure out what I need to get when I get motivated. I do appreciate the offer for you to disassemble your radio just to find this out for me. I have one more question about the filter option. The radio is supposed to take six filters and four are provided. I assume that their are two open positions on the main board and that they are for small sized filters. AOR has an optional filter board and as long as I want to install two more small type filters I further assume that I don't need to buy this daughter filter board. I expect that this optional daughter filter board is for the large mechanical filters. -- Telamon Ventura, California |
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