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ATTIC ANTENNAS
On VHF a beam antenna can work well in the attic, even a rotator can be used. Again stay away from metal and wires to maintain your pattern. On HF wire beams can be run on the roof supports or the rafters, these usually are good for one direction only but can be YAGIMAX - IW5EDI SIMONE - HAM-RADIO YagiMax. Posted in Ham Radio Software. Even if outdated, is still a good program to calculate and desing yagi antennas elements dimensions, sizing and spacing. I’ve used it to verify some antenna plans I’ve found on the net. It’s particularity is that you atfirst need to
SWISS QUAD ANTENNA
The dual-gamma is made of two aluminum rods, 1m long and 2mm diameter (not crucial) The two rods are drilled at one end, these ends slide inside the rubber seals and then are connected together by means of an aluminum corner plate 10x10x1.5. (photos) On 28Mhz, two capacitors in parallel – variable 60pF + fixed 60pF – are connected between HOW ANTENNA TRAPS WORK The trap is situated 1/4 wave length from the boom of a yagi and is similar to that of an open switch. The same electric circuit is present on 10 meters. Conversely, the 14 MHZ signal perceives the 21 and 28 MHZ traps as a closed switches at 14 MHZ. The 20 meter signal and uses the whole length of the element. TYPICAL TRAP FOR20–15–10
THE VERTICAL BAZOOKA ANTENNA 2M CROSSED YAGI ANTENNA 2m crossed yagi antenna. This 2m yagi uses design data from DK72B’s excellent yagi website. The element to boom mounting used here may be of use to some as it does not use any polamid mounting / insulating clamps at a cost of 2 euro each ( this is a 7 el crossed Yagi so twelve clamps would be needed ). The photographs show how the 12mm diaTHE GAMMA MATCH
The Gamma match is the most used matching device used for yagi beams. What it does is: A Yagi almost never has an impedance of 50 ohms. In other chapters i told that Gain, bandwith, F/B etc. all relate to eachother these figures are never all high at one point. INSTRUCTIONS FOR PUTTING UP A LONG-WIRE ANTENNA Tie the other end of the nylon rope to each insulator. The bare copper wire is strung from between the insulators, as shown in the diagram. Use an insulated wire to connect to the copper wire at the end closest to your radio. Strip a couple inches of it and wrap it around the bare copper wire. For best results, solder this connection. KENWOOD TS-570D RCP-2 SOFTWARE Licensed Amateur Radio operator in 1996 as IW5EDI, active member of ARI Firenze and ARRL; Class 1970, married with two childrens, love experimenting and antenna home-brewing. W5GI MYSTERY ANTENNA The W5GI Multi-band Mystery Antenna is a fundamentally a collinear antenna comprising three half waves in-phase on 20 meters with a half-wave 20 meter line transformer. It may sound and look like a G5RV but it is a substantially different antenna on 20 meters. Louis Varney’s antenna, although three half waves long, was an out-of-phase aerial. Mr.ATTIC ANTENNAS
On VHF a beam antenna can work well in the attic, even a rotator can be used. Again stay away from metal and wires to maintain your pattern. On HF wire beams can be run on the roof supports or the rafters, these usually are good for one direction only but can be YAGIMAX - IW5EDI SIMONE - HAM-RADIO YagiMax. Posted in Ham Radio Software. Even if outdated, is still a good program to calculate and desing yagi antennas elements dimensions, sizing and spacing. I’ve used it to verify some antenna plans I’ve found on the net. It’s particularity is that you atfirst need to
SWISS QUAD ANTENNA
The dual-gamma is made of two aluminum rods, 1m long and 2mm diameter (not crucial) The two rods are drilled at one end, these ends slide inside the rubber seals and then are connected together by means of an aluminum corner plate 10x10x1.5. (photos) On 28Mhz, two capacitors in parallel – variable 60pF + fixed 60pF – are connected between HOW ANTENNA TRAPS WORK The trap is situated 1/4 wave length from the boom of a yagi and is similar to that of an open switch. The same electric circuit is present on 10 meters. Conversely, the 14 MHZ signal perceives the 21 and 28 MHZ traps as a closed switches at 14 MHZ. The 20 meter signal and uses the whole length of the element. TYPICAL TRAP FOR20–15–10
THE VERTICAL BAZOOKA ANTENNA 2M CROSSED YAGI ANTENNA 2m crossed yagi antenna. This 2m yagi uses design data from DK72B’s excellent yagi website. The element to boom mounting used here may be of use to some as it does not use any polamid mounting / insulating clamps at a cost of 2 euro each ( this is a 7 el crossed Yagi so twelve clamps would be needed ). The photographs show how the 12mm diaTHE GAMMA MATCH
The Gamma match is the most used matching device used for yagi beams. What it does is: A Yagi almost never has an impedance of 50 ohms. In other chapters i told that Gain, bandwith, F/B etc. all relate to eachother these figures are never all high at one point. INSTRUCTIONS FOR PUTTING UP A LONG-WIRE ANTENNA Tie the other end of the nylon rope to each insulator. The bare copper wire is strung from between the insulators, as shown in the diagram. Use an insulated wire to connect to the copper wire at the end closest to your radio. Strip a couple inches of it and wrap it around the bare copper wire. For best results, solder this connection. KENWOOD TS-570D RCP-2 SOFTWARE Licensed Amateur Radio operator in 1996 as IW5EDI, active member of ARI Firenze and ARRL; Class 1970, married with two childrens, love experimenting and antenna home-brewing.IW5EDI SIMONE
If you have issues on selecting the USB Port or you have multiple one, check the status of the USB connections with lsusb command. pi@raspberrypi:~ $ lsusb Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 0d8c:013c C-Media Electronics, Inc. CM108 Audio Controller Bus 001 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port Bus 001HAM RADIO DELUXE 5
Ham Radio Deluxe, a software suite for ham radio operators, become quickly popular among the amateur radio community thanks to the powerfullness of it’s features.. Born mainly as a radio-control tool with the CAT commands interface, it has been joined by a complete log-book tool, and a complete multimode decoding/encoding system named Digital Master 780, and many other accessories like rotor MAGNETIC LOOP CALCULATOR Magnetic Loop Calculator v.1.6 by KI6GD. It’s a light magnetic loop antenna calculator that run on MS Windows, and allow to calculate capacitor values and voltage based on Loop circumference, conductor diameter, desired resonant frequency and the operating power. Works either in Standard and Metric units, and let you choose on material, and loop shape, as circular, square or octagon. 2M CROSSED YAGI ANTENNA 2m crossed yagi antenna. This 2m yagi uses design data from DK72B’s excellent yagi website. The element to boom mounting used here may be of use to some as it does not use any polamid mounting / insulating clamps at a cost of 2 euro each ( this is a 7 el crossed Yagi so twelve clamps would be needed ). The photographs show how the 12mm dia THE VERTICAL BAZOOKA ANTENNA The Vertical Bazooka is easily tuned by clipping short sections from the end of the exposed center conductor of the antenna. There are, however, some precautions you must observe. This is a dipole, which means it has easily disturbed high impedance nodes at both the tip of the top section and the bottom of the braid. HALO ANTENNA FOR 70MHZ Concepts The halo is an omni-directional antenna with horizontal polarization. This is practically a horizontal loop, namely a half-wave folded dipole, with its endings slightly separated. The feeding is done through a system called gamma-match with the condenser obtained by inserting the central core of rg58 cable including the insulator, inside the aluminum tube thatRead More YAESU FT-857D REVIEW Yaesu FT-857D Review. The Yaesu FT-857 is a little marvel. Crammed into the enclosure is an MF, HF, VHF and UHF transceiver with most of the modern bells and whistles that anyone could want, and which can supply 100 watts on 160-6 meters, 50 watts on 2 meters, and 20 watts on the 440 MHz band. It is capable of operating in the CW, AM, SSB, FM COBWEBB 5 BAND ANTENNA It is basically a 5 band antenna comprising of 5 full half wave dipoles for each band – between 10M & 20M. As an added bonus, the antenna is also resonant on 6M!! Each dipole leg is made from twin cable and fed with 50ohm coax. It is Omni directional and cost about 40.00 to build. I don’t know how much power it will take except tosay it
CALCULATE YOUR ANTENNA GAIN More than ten years ago a humorous article on antenna gain was published in the ham radio magazine “QRV.” The article stated that there are three kinds of gain: 1. the dB/d and dB/i gain based on CCIR regulations (the true and honest real gain!)2. the “dB/ham radiogain,” which is
W2BRI - AN EASY GUIDE TO HOW TO BUILD YOUR OWN MAGNETIC LOOP W2BRI - An Easy Guide to How to Build Your Own Magnetic Loop Page 4 of 19 2. Soldering the Joint: Soldering is about using indirect heat, not direct heat. So when you turn on your torch and apply heat to the pipe, apply heat slightly off the center of where you intend to putyour
Amateur Radio news from Italy IW5EDI SIMONE – HAM-RADIO*
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* 144 / 430 Dual Band J-pole antenna * 10 Meter 4 Element Quad Antenna * 144 Mhz Magnetic Loop Antenna * A “loopy” Loop Loaded Vertical * W5GI Mystery Antenna * A Multiband Dipole * Build a W3DZZ Antenna * A portable 2-element VHF yagi * Assembling GAP Titan DX Antenna* The Galaxy Dipole
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* Hexbeam antenna setup * W4TI Rotor Installation DOUBLE BAZOOKA ANTENNA FOR 40 METERS Posted in Antenna Theory,
HamRadio ,
HF Antennas
1
Comment
Planning to setup a double bazooka antenna for 7 MHz during next months to verify performance of the Gap Titan DX on that band. I feel like the GAP is not so well performing on that band and I’m goint to setup for the CW portion of the 40 meters. This is the basic schema I’m going to follow40 meter bazooka
double bazooka
PLAYING WITH THE GRAPHIC TABLETPosted in Articles
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Santa recently dropped this lovely gift to my son….. Well, I had to learn a little bit about how to use it before I taughthim.
I got inspired by the IARU World Amateur Radio Day leafleft.. SHORT VERTICAL FOR 160 METERS BY I5CDF Posted in HF AntennasLeave
a comment
Here a short vertical antenna for top band, designed by I5CDF Riccardo Rossi for IK5TBK Stefano.160 meters 160m
I5CDF
vertical antenna
FLRIG ON RASPBERRY PI4 AS RTX DIRECTOR FOR MAC OS APPSPosted in How to
, How
to
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I’ve recently introduced a Raspberry PI 4 as main remote RTX controller for my Kenwood TS-590s. This allows me to control the Kenwood TS-590S from the iMac simultaneously with several applications, including RUMLOG, FLDIGI,WSJT-X.
THE ISSUE
Could not control simultaneously my transceiver directly from two or more applications. Additionally remote connection from the internet requires a PC always turned on or at least the possibilty to power onwith wake-on-lan
CAUSE
The usage of the USB Port is exclusiveWORKAROUND
An alternative solution is to run the FLRIG on the iMac, and connect the applications to the local loopback 127.0.0.1. I’m using RUMLOG by DL2RUM as main logging program both as main logging and for contest logging as well. FLDIGI for common digital modes andWSJT-X for weak
signals digital modes.WHAT DO YOU NEED
ON THE MAC you need to reconfigure the programs, in order to use FLRIG as Radio. Basically FLRG acts as a gateway to your radio. RUMLOG CONFIGURATION FLDIGI CONFIGURATION WSJT-X CONFIGURATION On the RASPBERRY you need to configure the connection with the USB to Serial cable connected to the RS-232 port of the TS-590S. I had to select NONE as PTT port to get rid of the “Select Separate ports” error message If you have issues on selecting the USB Port or you have multiple one, check the status of the USB connections with LSUSB command pi@raspberrypi:~ $ lsusb Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 0d8c:013c C-Media Electronics, Inc. CM108 Audio Controller Bus 001 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hubfldigi flrig
iMac
raspberry
rumlog
TS-590
4 ELEMENT YAGI FOR 6 METERS Posted in VHF AntennasLeave a comment
DIMENTIONS
ELEMENTS
A, B, C
SPACING BETWEEN ELEMENTS 119.38 CMS.E 1
REFLECTOR 1: 304,8 CMS.E 2
RADIATOR : 274,32 CMS.E 3
DIRECTOR : 271,15 CMS.E 4
DIRECTOR: 269,24 cms.D
DISTANCE WITH GAMMA MATCH: 35, 56 CMS APROX.E
GAMMA SPACING: 7,62 CMS.F
GAMMA TUNE: 50,8 CMS X 12,5 MM DIAMETER Elements are 12,5 mms.diameter Inside the F part, insert an RG213 The sheath is introduced inside F with a 30.48 cm RG213 The Boom is built with a 5 cm rectangular aluminum tube. wide by 7.5 cms. High.6 meter
SOME PLAIN FACTS ABOUT MULTIBAND VERTICAL ANTENNAS Posted in Antenna TheoryLeave a comment
By Lew McCoy, W1ICP
_QST_ September 1972, pp. 14-16, 28 DURING DISCUSSIONS with newcomers, and old timers for that matter, it becomes apparent that there is considerable confusion as to what exactly a multiband vertical antenna is. The confusion concerns the method of feed, how much mismatch one can expect, how many radials are required, how the particular antenna is built for multiband use, plussome other points.
This article breaks the subject into simple language and provides the reader with sufficient expertise to assure him that he won’t wind up with a system he really doesn’t want Before going into a discussion of the different types of multiband “verticals” we will offer some simple antenna facts._SOME BASIC THEORY_
The term “multiband antenna” has come to mean many things to hams. With trap antennas, tapped coils, random wires, and so forth, there is plenty of reason for the confusion. Simply, a multiband antenna is one that can be used on more than one band. How we make it work on different bands is another story.Continue reading→
vertical antenna
verticals
THE CLEMENS MATCH
Posted in Antenna Theory,
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The Clemens match is easy to make and reliable, and is preferable to a single Gamma match as it is balanced. I was first introduced to the Clemens match by G4IGO several years ago, Ken builds his in a slightly different way by putting the capacitor at the feeder end and connecting the far end directly to the boom. Both methods appear to work equally well. The cable clips used are the black polythene types used to secure steel wire armoured cable to walls etc. The length of the copper tube for matching at 50.110 MHz is 5.98683 metres * 0.125 = 0.748 metre or 29.455inches. Put the Clemens match on the underside of the driven element to prevent large birds from damaging it. I think it is preferable to connect the feeder braid to the centre point of the dipole also, as this helps to prevent unwanted currents flowing in the outer back to the tx. Water proofing the joints etc. is very easy if plenty of polyeurothane varnish is painted on to them. This must be checked yearly to check for any signs of cracking or flaking. I use LDF250 feeder from my rotator to the Clemens as this makes construction very easy. The outer plastic sheath is stripped from where the coax joins the dipole element. This gives continuous contact of the outer with the element all of the way along. Once liberally painted with clear polyeurothane varnish it is totally water proof, and corrosion will not take place. Tuning is a matter of starting with the copper tube about 4 inches (10cm) away from the driven element, with loop of RG58 inner soldered to the copper tube at one end, and to the inner of the feeder at the other end. Attach another length of RG58 inner to the driven element at the other end of the copper tube. Make it about 12 inches (30cm) long. I secure it to the element by trapping it under a stainless steel jubilee clip. Using an antenna analyzer, (or low power tx and swr bridge) set to the design resonant frequency of the antenna. Push the RG58 inner into the copper tube until a dip in the swr is seen, then move the copper tube nearer to the driven element by a few mm. Move the RG58 in or out of the copper tube until a further dip an the swr is seen. Continue this process of moving the copper tube, and moving the RG58 inner in the tube until the lowest possible swr is obtained. Trim the lengths of the RG58 at each end if the loops in them become too large, until the final setting is arrived at. Finally, if you have left the driven element length slightly long as suggested, trim it by removing 1mm or so from each end and retuning the Clemens to the lowest possible swr. Do this very carefully, as you cannot easily make the driven element longer again if you cut it too short. This process should be carried out with the antenna mounted so the reflector is 2 to 3 feet (55 to 90cm) from the ground and the rest of the antenna pointing at the sky. Next, before you finalize the Clemens, hoist the antenna in the air and find out how far the resonant frequency has moved. It usually drops by 50 to 100KHz. For this reason it is better to tune the antenna initially at a frequency of 50.210 MHz (for instance) so that when in the air the antenna is at the correct resonant frequency. This prevents the need to hoist the antenna up and down several times. If you are satisfied that all is well, having connected the antenna to the feeder that will be used, and checking that the swr measured at the rig in the shack is no different to that obtained when tuning near the antenna. You can then substitute the pieces of RG58 inner used for tuning by a couple of new pieces cut to the correct lengths. make sure the loops at the ends are not excessive. Once every thing is in place, paint all the joints and exposed coax ends with a liberal amount of polyeurothane varnish. Do not paint the whole length of the copper tube as the resonant frequency of the matching will be moved slightly by the dielectric constant of the varnish. Check, and check again that the swr is ok (it should be 1:1). Once satisfied you can install the antenna in it’s final position. The resonant frequency will alter slightly in wet weather and will tend to drop a few KHz.Antenna match
SWL LONGWIRES
Posted in shortwave
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Taken from a usenet post by John Doty in 1996 In article <9612182335114148@mogur.com> len.anderson@mogur.com (LenAnderson) writes:
_> TV>> I wonder if a longwire balun would help match the impedance &provide a
> TV>> better signal?_ > No, it will (primarily) change only the magnitude of the antenna > impedance over frequency. Some bands will have more sensitivity than > other bands. The antenna tuner will take care of that. Actually, a fixed matching transformer can dramatically reduce the wild swings in antenna efficiency that a coax fed wire antenna exhibits. Let us calculate: The following graphs are based on a 15 meter vertical antenna, fed at ground level, using a conical approximation. The antenna’s characteristic impedance is assumed to be 620 ohms, which is typical for a thin wire. For more on the conical approximation, see Chapter 8 of “Antennas” by John D. Kraus (McGraw-Hill, 1950). The first graph is for an antenna fed directly from 50 ohm coax. The horizontal axis is the frequency in MHz, the vertical axis is the mismatch loss in dB. The well known “quarter wave” resonances near 5, 15 and 25 MHz are visible as sharp peaks where the mismatch loss closely approaches zero. The second graph assumes a matching transformer with a 9:1 impedance ratio at the feedpoint, presenting the antenna with a load resistance of 450 ohms. At most frequencies, the mismatch losses are considerably lower for this case. The variation in the mismatch loss is alsoreduced:
Well, so what? In the absence of interference, the signal to noise ratio is the main determining factor for the audio quality of thesignal.
The mismatch loss affects both signals and noise, so if the receiver was noiseless the losses would not affect the signal to noise ratio. Real receivers, however, are not noiseless: if the loss is too high, receiver noise will become dominant, and overally system sensitivitywill suffer.
The following results assume cosmic noise of 29 dB above thermal at 10 MHz, declining with increasing frequency at -23 dB per decade. No man made or atmosperic noise is assumed. I assume a receiver noise figureof 10 dB.
First, here is the signal to noise impact of the mismatch losses for a 50 ohm coax feed without a transformer: Losses in signal to noise of 3-5 dB are likely to be noticeable. The largest impact is in the quiet bands above 15 MHz. On the other hand: the loss in signal to noise with a 450 ohm feed ismuch smaller:
You are unlikely to be able to notice losses in signal to noise inthis range.
The results depend on the assumptions. A real longwire isn’t usually vertical: this tends to degrade its performance a bit at the low frequency end, while improving it at high frequencies. This is good, because in the model the signal to noise is declining as the frequency increases: the increase in performance cancels part of this. No man made or atmospheric noise is included. If they are significant, the precision of the match becomes less critical. Man made noise can be significant at any frequency, but atmospheric noise is more significant at the lower frequencies. A receiver noise figure of 10 dB is mediocre for a solid state receiver or a tube receiver with a triode RF amplifier. Tube receivers with pentode RF stages may be a bit worse than this, and something like a Hallicrafters “Sky Buddy” (no RF stage, pentagrid converter) might have a noise figure >30 dB. The better (smaller) the noise figure, the less you have to worry about matching. Sky Buddy owners will want to tune their antennas very carefully. I haven’t included cable losses here. These are not terribly important unless you’re using an ATU at the receiver end. If you are, using a fixed transformer to get the match roughly right at the antenna end will reduce the cable losses, because cable losses increase with increasing SWR. My own experience concurs with the results of this theoretical analysis (or I wouldn’t be writing about it: I’d be trying to figure out what was wrong!). I have experienced “deaf bands” with coax fed antennas lacking matching transformers, but my transformer-fed antennas work well across the HF spectrum (and even down to longwave). I don’t bother with an ATU.shortwave SWL
HALO FOR 6 METERS BAND Posted in VHF AntennasLeave a comment
A good antenna that can be used for the car as well as the house is an HALO. This antenna maintains good omni-directional horizontal polarization. Basically the antenna is a half wave dipole bent into a circle,BUT shorter than a dipole for this frequency. The circumference is 60-70 inches. By useing the gamma match (see above) you can use regular coax.This is a high-Q antenna.So bandwidth is about 200khz. (Perfect for 50.100-50.200 where most of the 6m ssb activity is) The 2 large discs can be about 4-5 inches round and the small disc about 1.5 inches. Mount the 2 larger discs at the ends of the halo by screwing end caps to the center of them and then the end caps will go over the ends of the halo. Next drill a small hole in one of the larger discs and the same size hole in the exact center of the small disc. Put a 2 inch bolt threw the center and run a nut up the bolt to lock it in place. Then a nut on each side of the large disc to secure the bolt to the larger disc. Mount the gamma rod the same as you did on the beam (see above) BUT bend the gamma to match the curve in the halo. Finally take three 2-3 inch nylon spacers and mount them between the large discs. You should drill 3 holes in a trianle patern and use 3 nylon bolts and nuts. This will ensure that the ends plates do not move around on you. You can mount this antenna on a mast by making some type of bracket for support. (Just try to put the bracket by the mount where the coax/gamma is so that the mount should not affect the antenna preformance.) To match the antenna simply move the gamma around a few times(move it in small increments it really tough). Once you get the S.W.R. down below 3:1 then move the small disc by loosening the nut and turning the small disc.(AGAIN move it in small increments)6m
6M J-POLE BY WB5CXC
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Use a 54” piece of 450 ohm Ladder line. Cut out 3 inches of the center part of the ladder line. Solder a PL-259 on the bottom of the Ladder Line (both side of the ladder line will solder on the ground side of the PL-259 – this is used for the shorted part of the J-Pole). Cut a 1” PVC pipe 1 1/2” long. Cut a 36” piece of RG-174 coax. Wrap the coax around the PVC pipe. One end will attach to the PL-259, the center of the coax will connect to the center of the PL-259 and the shield of the coax will connect to the outer portion of the PL-259. Strip the insulation off lh ladder line 2 1/2” above the PL-259. Attach the center of the coax to the side that will have the long wire attached, the shield side of the coax will connect to the short sideof the J- Pole.
Connect the Long wire to the ladder line. Check the SWR, if it is not less than 2:1 in the operating portion you want to operate, you can tune the J-Pole by moving the tape of RG-174 up or down. Do not move it more than ~ 1/4” at a time Article originally available at http://www.wb5cxc.com/6m_jpole.html50 MHz 6m
j-pole
IW5EDI SIMONE
* Licensed Amateur Radio operator in 1996 as IW5EDI, active member of ARI Firenze and ARRL * Class 1970, married with two childrens, love experimenting and antenna home-brewing. IT System Engineer, recently started having fun with morse code and Raspberry PiIW5EDI Simone
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