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"Dave's Miscellaneous "Tidbit" Radio Stuff"

Area for just about "anything" to do with radio receiver's / amateur transceiver's but not in any huge detail.
 Includes guest reviews.
enjoy......Dave N9EWO

I will NOT be held responsible for any info that is listed here

HF RFI Generator - "Electronic Defrost Timer" : We had a defrost timer replaced in a near 20 year old refrigerator. The mechanical one that was in it was replaced by the Supco model UET120 which is of a solid state design. It creates some pretty nasty SW/HF interference with it's internal switching power supply (as I was afraid of). But it could have been worse. It’s RF noise in my situation (and is at a pretty major level) is between 2200 and 4000 kHz. It drops off greatly after that with only a very low level spur or harmonics above up to around 20 MHz.
Thomas Witherspoon of "The SWLing" reports to me that between his refrigerator and freezer are the 2 worst HF RFI generators in his house. It appears that all new refrigerators / freezers are using these "el-cheapo" Chinese solid state "Defrost" timers now. These might seem more robust, but as I read around the internet they are not. Guessing are more prone to failure from spikes/power line surges ? Yeah, the new DX catch....the neighbors refrigerator.
Thank goodness I still have the MFJ-1026 device at HQ in case it gets too bad, but that is pain to have to deal with.

  More nasty household appliance RFI woes for HF reception.
This time it's a "Solid State" Refrigerator Defrost Timer. We experienced this UET120 model by Supco.

Yaesu FT-70D Notes : A few notes from our Yaesu FT-70DR "Fusion" test sample hand held transceiver (sorry we are not planning a review on this radio).

- Operates well enough all around with plenty of decent undistorted receive audio.
- Fusion "Yahoo Groups" have reported excessive receive failures since it's release, that is internal speaker fails but still works with speaker mic OK.
- Internal microphone sensitivity between analog and fusion transmit audio is still far apart and Yaesu should consider separate TX level adjustments for digital and analog, otherwise TX punch is good.
- Very good ergonomics and very easy to see LCD display and backlighting.
- Many may not prefer the electronic volume control (The FT2DR has a top mounted dedicated volume control)
- No extended receive above 579.995 MHz (nor MW or FM broadcast).
- Receive coverage lacks SW broadcast (which the FT2DR has, AM mode only).
- The biggest "Bug-A-Boo" with the FT-70DR involves "stand by" current when off. Many Chinese handhelds suffer from this bug and the Japanese made Yaesu FT-70D is nasty BAD here as well in our testing. It's receive current consumption in regular operation is not so great either even with it's RX LED's off and battery saver in use and this is even in analog mode (the FT-2DR fares MUCH better here in the specifications). ONLY way around the excessive "stand by current" bug is to totally remove the battery when not in use (a royal pain in the rump !). Yes, this is even after the recommended firmware update !
- Cabinet is on the "chubby wide" side. For anyone with small hands you know what I mean. Not easily placed in ones shirt pocket either (unless you are a lumberjack).
- Included plastic antenna continues the Yaesu tradition here (that is a bit on the "ugly-thugly" side and only so-so performance).

Nice low cost Fusion handheld, but with it's battery wows / current consumption, in our view one is best to consider the more expensive FT-2DR even with it's older design CD-41 external charger option that suffers from a extremely high failure rate (very sensitive to ESD damage). Note : We have NOT tested the FT2DR model. For analog use we MUCH prefer the "totally FCC legal" Chinese TDXone TD-Q8A which we still use at HQ and has no standby current ills and performs similar (and is MUCH smaller). But sadly is no longer easily available in the USA.  To see FT-70DR eham reviews click here.

The Yaesu FT-70DR "Fusion" Dual Band Handheld (left). (Yaesu Photo's)
In our view one should consider the FT2DR model (right) instead (see text above).

N9EWO Review :
Indoor FM Antenna

C.Crane's "FM REFLECT" Indoor FM Wall Antenna (it's outer box photo above).
100% Passive and Respectable. Made in China. (sorry no longer available new) (N9EWO Photo)

Discontinued Product

PRO : Improves FM Broadcast reception over the standard T-style dipole that was included with older Stereo receivers. Passive design for excellent signal to noise ratio. Design is much less affected by people moving around in the room (a major issue with any indoor antenna). 8 foot 75 ohm coax feedline (no 300 ohm twin lead feeds lines used here). Mounting ears and center section that have nail mounting holes (required to use, see con). All white color. Includes a 75 to 300 ohm transformer.

CON : Wall mounted antenna, generally ugly and difficult to hide, must be mounted to something and is not easy to deal with with it's thick elements. Stiff coax cable. Pricey for what it is (at full price). Heat shrink piece over coax connector was not done properly and made for difficult connection to receiver (one can just carefully remove it with a pair of scissors). As it is with any indoor antenna some experimentation may be required to locate the best hot spot in the room (may require an extension of the coax cable). The weird whip portable antenna connection with the provided 75 to 300 ohm balun and alligator clip did NOT provide any improvement in our testing (we say any host receiver MUST have an actual antenna and ground connection, 75 or 300 ohm).

Final Word : This 54 inch "INDOOR" FM broadcast antenna was a winner in our tests. After trying many indoor FM antenna's over the years, this one works and no fiddling with some phasing control. We tested this in a horizontal configuration (see photo below). Not that it will make the weak station jump to full scale signals (it can't and doesn't). But when directly compared to a dipole antenna that were included with older stereo receivers from years past (not a folded dipole type), the C.Crane FM REFLECT was definitely an improvement (on a some stations it was quite surprising). Completely passive design, this is NOT another and undesirable active antenna either (designs which we don't bother with anymore at all), so NO added noise to the signal. We found it worked equally well across the entire FM broadcast band (88 to 108 MHz). A bit ugly yes, but is still easier to hide over a even more ugly pair of "Rabbit Ears".

Sadly this antenna has been discontinued and no longer available new.

Dave N9EWO
N9EWO, all rights reserved
ver 2.1

The C.Crane "FM Reflect" is a bit on the unwieldy side and is less stiff than one would hope for. We mounted the test sample on the top of 2 bulletin boards with it's feedline coax neatly hidden in the space between them. There are TINY mounting holes at each end and a couple in the middle, but to use these will take a fairy long and thin nail etc. Being as "thugly" as it is, it cannot be used without some mounting support (must be wall mounted). In testing it would have been nice to have seen the coax slightly longer than it's 8 feet (say 10 to 12). But is easily lengthened (the shorter the better of course.) (N9EWO Photo)

 Guest Review :
  Grundig / Eton "Field" BT (Bluetooth) Receiver
Craig Menning guest "micro review" on the Grundig / Eton "Field" Receiver (many thanks Craig)

 It now has Bluetooth support with the new BT model. Appears the speaker sound has radically changed over the old non-BT version. There has been a change to the bass response through headphones. At "maximum" Bass adjustment, the new version has much less low end. Similar, but not so obvious results with the speaker.
Eton Field : Current readings in AM and FM, no signal, minimum volume (in mA's)
                         With LED Backlight ON - OFF                                    
                     AM/on    AM/off     FM/on     FM/off
OLD Field     102          60          102          60
NEW BT        118          76          116          74
As you can see the LED backlight adds 42 mA, something to be avoided. The new radio seems to draw 14-16 mA more than the old one. Box covering the speaker in the new BT version, precluding the conversion to a longer AM antenna. Will update this as necessary as Craig learns more with his comparisons.
On AM (MW) , the new Field and the old version are basically the same. Some minor sensitivity differences could be seen on a few frequencies, but not enough to say one radio was more sensitive than the other. On FM, for the most part they were the same, but there were a few stations that came in better on the old radio. On shortwave, using the whip both radios are the same, for the most part. Around 15 MHz, the new BT version did slightly better. My revised opinion, from a general shortwave standpoint is these radios are the same. Naturally adding a wire antenna helps greatly.
Contrast on the new radio's display is better, I also observe that backlight on the buttons is better. I wish the display could be seen with the LEDS off (with any negative type LCD display this is not possible…N9EWO).  One comment common to both radios is the tuning is terrible. The two speed tuning is annoying.
Another observation, on AM, the older version had birdies / hets / whistles on four different frequencies. The new version only had one. This is an improvement. I wonder if the new added shielding was a factor ? The station had to be extremely weak, barely audible for these to be observed. With stronger signals, they are not noticeable.
I did notice that, on the old version, the audio could get louder. This could be due to the difference between a 4-inch speaker and a sub-two inch speaker. Or, there could be other differences?
Conclusion: I wouldn’t get the new version expecting an improvement in signal reception. Given that the old one likely has better battery life, I’d say that is the better choice. Since both old and new would allow adding the jack for alternate AM antennas, anyone wishing to do that could go with either radio.

Craig Menning

 Guest Review :
 CommRadio  CR-1A Communicatons Receiver 
Dean Bianco guest "micro review" on the CommRadio CR-1A Communications Receiver (many thanks Dean)

Discontinued Receiver

Solid build-quality (case made of steel), Crisp, powerful audio output (especially when connected to an outboard speaker), Manually dimmable, clear OLED display with EMI-filtered lens. 12-14 Hour "Lithium Ion" battery capacity between charges (see Con). Menu-driven operating features no too difficult to master (see Con), External Power Supply (Wall Wart) runs cool and is quiet [this was not normally provided with the receiver.....N9EWO]. Very portable, and the over-sized rubber feet make the radio very stable on the operating surface.

Fair dynamic range with any decent outdoor antenna and no attenuator to help control it . Sub optimal image rejection. Clumsy menu system. Hard wired internal battery [Note : This was a later production sample, the battery holder used in earlier product had been removed....N9EWO]. No Synchronous  Detector (see text). No Performance Upgrades since it's release. Poor IF filter symmetry.  Lacking DSP Noise Blanker, DSP noise blanker, Pass Band Tuning (PBT) and Notch Filter.

Dynamic Range is only fair when using a high-performance outdoor antenna. There is no Attenuator to help tame it. Image rejection is rather sub-optimal---e.g. strong signals  appearing on frequencies where they are not supposed to be ("Brother Stair everywhere" and Radio Havana Cuba, among other high-signal strength stations) on par with the image rejection specs of cheap portables !! The menu system's functionality is cumbersome on some functions, making manual signal tuning a chore. Internal batteries are hard-wired [is not a standard type either...and is missing a line audio output jack...N9EWO] . No synchronous AM detection (see next paragraph).

The manufacturer never made any performance upgrades during it's life on the market. They even hinted at offering SYNCHRONOUS DETECTION among other features, but was never implemented. (Hardware changes to the antenna inputs and added PC -accessible GUI and real-time Spectral Display [computer-based only] not withstanding).
The IF bandwidth filters, while sharp and clean and a good number of them, have poor symmetry--i.e., one side of a signal, say, as an example on AM at any bandwidth, the lower side is wider than the higher side, compromising selectivity when trying to tune away from a close-in adjacent signal a few kHz away.

There is
No DSP Noise Blanker,  No DSP Noise Reduction mitigation, No PBT, No Notch Filtering.

Overall, the CR-1a (priced new at $550 to $600) while tank-tough, easily portable, sensitive, and great sounding, alas, is (was) too expensive for its limited feature-set and functionality performance compromises. 

Dean Bianco

"Caveat Emptor" : JRC Display Failures

Display failures are now very common with the JRC NRD-525, NRD-535 Receivers and even with the JRC JST-135 Transceiver. These radios all use a "custom made" florescent type display and now being quite aged are suffering from ever weakening brightness and then just failing completely in time. They have not held up well with age. One could TRY and replace the 4 high voltage (35 to 50 volt) electrolytic capacitors in the display DC-DC converter circuit, but usually when these go out.....that's it (it turns into a great doorstop or computer controlled only set) new parts are available anymore.  So a "MAJOR" Caveat Emptor (buyer beware) if you are considering any used sample for purchase !!

The later NRD-545 Receiver (plus the JST-145 and JST-245 Transceivers) uses a negative LCD with a "CCFL" (cold cathode florescent tube) back light. With it's ever increasing age are also subject to become weak and in time total failure. Just as with the more elder JRC sets , parts and repair from JRC are no longer available. So once this tube fails, it becomes a computer controlled only receiver unless a owner workaround is figured out (some other way to back light the LCD and or substitute parts) ??

A general reminder, as it goes with all vintage "solid state" radio receivers / transceivers one should be aware any major ills of any certain used model before a purchase. Check it out throughly before and then cross your fingers after.

AOR AR7030 Power Supply Repair Notes

Added power supply repair notes to the AOR AR7030 Page. Yes, our 7030's power supply failed and now repaired / back to normal . In our case were getting a BAD hum when turned off. Also the normal "thump" that happens when turning it off was no longer .
See the AR7030 web page for more information (located about 3/4 way down the page), includes a few pictures .

Yes, our AOR AR7030 power supply failed and now repaired / back to normal .
See the AR7030 web page for more information (located about 3/4 way down the page) .

Tecsun PL-380 Undocumented Function Discovery
  Hiss Issues Apparently Cleared Up ?

 Jack W8ADQ informs us of a Undocumented Function with the Tecsun PL-380

1. With the radio OFF and showing the regular power off screen.
2. Press and hold down the [AM BW] button
3. After a couple of seconds it will do a display test and turn on all segments and annunciators.
4. Continue to hold the [AM BW] button down.
5. After another couple of seconds the 4 digit display area at the upper right of the LCD (not the main frequency display digits) will briefly show a four digit number.

This appears to be the firmware version. However this did NOT work with our 2011 made sample. But did with our early "hissy" 2014 one (display as 3808). Jack's newer 2015 sample displays 3809.

Our 2014 sample suffered badly from excessive audio amplifier hiss (in ONE channel with headphones and from the speaker). Was not just with my sample being defective as it this hiss bug has been reported elsewhere in good numbers.  But not with the 2011 test sample (is totally clean) hiss is ZERO. But Jack also tells us that the excessive hiss is ZERO with his his even later sample. Also other reports I have received from readers with LATE 2014 made samples and beyond are also now hiss free. So it appears that Tecsun has made quality control corrections to at least late 2014 samples and beyond ?? Our thanks to Jack W8ADQ for this information. 
Increased “Off” Battery Life with "Grundig G2 Reporter"
and Degen DE1126 - DE1127 - DE1128 - DE1128H

 Important Tip :

As out of the box default , when “OFF” , the Degen made Grundig G2 Reporter / Degen DE1126 / DE1127 / DE1128 / DE1128H portables have greatly increased standby current consumption for the clock display (when the tuning knob is rotated). So even when not being used the internal lithium battery charge will be completely depleted in a few weeks without even ANY use (this is normal).

To GREATLY improve battery life when “OFF” :

1. : Access the “System Set” menu (System Setting)
2. : Then select the “Power Off Mode”
3. : Toggle the default “Standby” setting over to “Sleep” mode (called “Hibernate” with some Degen sets).

This will greatly increase battery life when “OFF”. Note: The clock will no longer be accessible with the “Sleep-Hibernate” selection (when turning the encoder knob).
Also, if you remove the battery (or it goes totally dead) this setting will have to be redone, as it then defaults to "Standby Mode".

Kenwood R-1000 “39.545 Mhz” Display Repair

After years of operation the Kenwood R-1000 (our review can be seen here) can suffer a fixed 39.545 Mhz display and/or a dead radio/display (or it can just go wacky). First place is to check and re-solder solder joints at Q201 and Q203 on the small power supply / PLL board on the underside of the chassis. This is where connector # 12 is located. The two TO-220 devices mounted on the large heat sink and the PC board solder connections can work loose after many hot/cold cycles.

Just as important, be sure and touch up the solder joints involving connector # 12 and the four power rectifier diodes as well as these can cause for bad connections too. Especially so with pin one and two on connector # 12 as these are 5 volt pins closest to the heat sink. In extreme cases all electrolytic capacitors, Q201 and/or Q203 and/or the 4 power rectifiers may need to be replaced on this board. Beyond this, I cannot be of any additional help.

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