| KZ1S |
Rating:  |
2022-09-06 | |
| the best rig I have ever used |
Time Owned: more than 12 months. |
A little over a year ago I bought the HF-380 (essentially the same as a KF-380 which is limited to amateur bands) on ebay. Of course, it was listed as perfect, but on arrival it did not work very well. I was offered about half my money back and decided to keep the rig. It took me over a year to repair it; the first problems were simple (contact cleaning on VFO selector switch, etc.). The vexing problem came down to a weak PC board solder connection near the first mixer. This was probably a flaw from day one, and on further inspection of the rig, I do not believe it was ever used. It is simply too clean, and none of the connector show any wear at all. I only noticed this when the rig really came alive and was a potential replacement for my current station. The rig had lots of obvious previous work done in searching for this flaw, I added to that, it's easy to see that components were changed etc. but no-one ever got close to the real problem.
There are two issues that make the HF-380 a bit obsolete, one is the phase noise in not state of the art, although it is not bad. I measured it in my lab where I have access to the Agilent top-of-the-line synthesizers, and used those for the measurements. The noise is high close to the carrier, but falls off very fast. There are, I believe, three phase locked loops in the frequency synthesis, and they all have loop filters that employ the LF353 dual op amp. I used the quad of the same, LF347, and it suffers from what we called popcorn noise, and low frequency 1/f noise in general below 500 Hz. Maybe newly manufactured ones are better, but the ones in my HF-380 are original. In the early 1980's, I was using LF347s in the loop filter for an atomic magnetometer stabilized magnetic field, basically the same thing as a VCO, and we had trouble getting to the precision we needed. This translates to less than state of the art for the HF-380, but the phase noise is not bad, and the noise falls off rapidly away from the carrier. The LF353 are also used in the synthesizer voltage stabilization circuitry. With these, it simply is not possible to have low phase noise.
The HF-380 has an over controlled oscillator, and the calibration against WWV is within 5 Hz after sitting for 40+ years, apparently unused.
Second, it does not have full break-in cw. I don't mind but some would.
There is no roofing filter that apparently is now considered state of the art, however I have an AR-5000 running next to the HF-380. I don't have a high gain beam or anything like that but in a small pileup I can separate the signals better with the HF-380. With SSB, there is a narrow band filter 1.7 kHz, but the audio is fine. On CW, the variable pass band frequency works well for moving between very close received signals.
My HF-380 has all of the accessories (except keypad and antenna tuner). The noise blanker seems to work well but LORAN, what it apparently was built for, is gone so we don't need to worry about that. Also, all of the service bulletins were incorporated-- if one had paid for all of these, I can imagine it would have been more than half the cost of the rig itself. There are about 40 of them and some have an estimated labor time of 8 hours. Just taking the rig apart is time consuming, and fortunately I never had to remove the giant PC board that holds most of the circuitry. I bought a new, unstuffed, board from Surplus Sales, so I could see the traces on the opposite hidden side which was very useful during the troubleshooting.
Given my experience, and what others have written, it seems the HF and KWM-380 had manufacturing quality control issues. If you have a good high performing one with low-ish phase noise, you are lucky, as I am, but if you have a lemon, you could spend a year trying to find the problem, as I did. For me, it was worth the effort.
I also bypassed the receiver low pass filter which brings the receiver response to about 140 kHz but there it is limited by the minicircuits mixer. I forget exactly, but the spec is a lower frequency of around 500 kHz.
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| N2CVS |
Rating: |
2021-12-03 | |
| It was absolutely wonderful in 1980. |
Time Owned: 0 to 3 months. |
Sometime near 1980 I listened to a KWM-380 out on Long Island NY at a store. I didn't have the money. It was so much better than anything I had ever heard.
N2CVS |
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| KG9H |
Rating: |
2019-07-02 | |
| Excellent for its time |
Time Owned: more than 12 months. |
Picture yourself in June 1980, and you have a radio with 10Hz readout.
Think about that for a minute.
Turn the clock ahead 40 years and ... the KWM-380 still holds it's own.
The transmit and receive audio is still outstanding. On transmit it has "presence!"
Well done Art!
de Frank KG9H
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| N7WST |
Rating: |
2019-02-02 | |
| BEST OF THEM ALL |
Time Owned: more than 12 months. |
| My husband is very active with HF and has owned many HF radios over the past few decades. I'm a very casual operator and appreciate quality and simplicity. Out of all the HF radios available in the shack, the KWM-380 is my favorite. The audio is natural and a pleasure to listen to. What I appreciate the most with this radio is its simplicity to operate. No complicated or extensive menus, just a few knobs and buttons on the front of the radio is all that is needed. My experience is that I can adjust this radio to sound better than any other radio in the shack. People I speak to compliment me on my clean and clear audio too. Simply put, I choose this radio when it's my turn to operate. Lana |
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| W7MBR |
Rating: |
2019-01-31 | |
| KWM-380 = Excellent Transceiver |
Time Owned: 6 to 12 months. |
| I have a large collection of vacuum tube Collins Radios including the KWS-1, S-lines, the Gray Boxes and just recently a KWM-380. It almost seems like people either love or hate Collins Radios especially the fully solid state KWM-380. Boy does it take a beating from these individuals that I really don't think it deserves. Personally, I find my KWM-380 (converted to a HF-380 with all of the options) to be a very excellent radio. It has all of the basics including very good sensitivity, excellent selectivity with the crystal filters and pass band tuning, outstanding stability and very good overall performance including a respectable dynamic range. The build quality is far superior to the commercially available Ham Gear on the market today. Look at the gigantic rear heat sink and glass epoxy circuit boards loaded with high quality components to name just a few. Removing the antenna from the radio I see very little s-meter movement and quite low phase noise. No band switch with continuous tuning is handy and it was way ahead of its time with this feature. The simple panel layout with few controls only tells me of its superior design as intended by the Collins engineers. The receive audio is non fatiguing to listen to and with a simple modification the transmit audio can be very good as well. I find the pass band tuning quite excellent adding to the already decent selectivity. The CW note is clean and click free and can be made even better with a simple modification. The service manual is very detailed making repairs possible on a fairly complicated radio. As with all vintage electronics parts do go bad and some are difficult to find. This is a professional radio with great build quality and it's performance is certainly better than a 2 or 3 rating that I see it sometimes get. An honest 4.5 is more realistic in my opinion and I have been collecting radios for over 55 years. |
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| KM1H |
Rating: |
2018-05-27 | |
| Way past its useful years |
Time Owned: 0 to 3 months. |
A good technical advancement but horrible on the ham bands with excessive phase noise on TX and RX. It would have been fine on point to point well separated channelized commercial and government frequencies.
I serviced many and would never own one.
I also own and use a TS-950SD and the TX and RX performance is fantastic; I like working weak DX at the noise level plus heavy QRM and QRN and have compared it against just about everything out there. |
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| M0KKW |
Rating: |
2014-10-23 | |
| No longer useable |
Time Owned: more than 12 months. |
Once you've replaced the underrated tantalum capacitors, these are reliable.
Sadly, unless you live miles from towns, the filthy local oscillator limits the performance to that of one of the poorer performing Japanese rigs.
The speech processor is horrendously complex but useless.
The VFO knob has all the "feel" of a homebrewed varicap tuned direct conversion set.
Overall, I grew tired of using the Collins because of it's susceptibility to low levels of noise and lack of refinement.
No doubt these will continue to appreciate because of their rarity but just can't cope with today's bands.
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Earlier 5-star review posted by M0KKW on 2003-12-08
I bought my 380 with a synthesiser fault which I fixed for the cost of a CMOS chip (pennies) and am now thoroughly enjoying the rig.
The quality of construction and components used are excellent, and the ergonomics are superb. The recieve performance is, despite what I'd heard, very robust.I regularly use 40M for local working with a "cloudwarmer" quad and the European QRM can be a real headache with some rigs, but not the Collins.
My 380 lives with a TS850, JRC JST 100 and 125, and my old favourite FT7 and is now getting the most use of the lot alongside an Amp Supply LK450.
A very practical classic which will be going strong long after the ft1000s have fallen apart.
Bob M0KKW |
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| WW3KP |
Rating: |
2012-07-01 | |
| Great Transceiver |
Time Owned: 6 to 12 months. |
I have owned two KWM-380's I sold one about a year ago and regretted the decision. I now own Serial number 2224, which was sent back to the factory when it was new to get the HF-380 upgrades and modifications. Rockwell Collins stopped production at serial 2253 so this KWM-380/HF-380 had all of the service bulletins installed at time of production. This 380 also has all of the optional filters, noise Blanker, cooling fans, original Pipo keypad and Kiron memory adapter.
I have been licensed for 53 years and I have owned just about every receiver, transmitter and transceiver made including most of the new DSP rigs and I still use the HF-380 more often than my new rigs. The appeal is the simplicity of operation, the receiver is excellent, the filters are exceptional and it compares very favorably to my FTdx-9000d. The passband tuning is fabulous, I can not say enough about how enjoyable this transceiver is to operate. I get great audio reports on SSB and I used a 3db attenuator in line to drive my Alpha 9500 to about 1200 to 1400 watts PEP output. Note it is easy to over drive a high gain amp like and Alpha 9500 so an attenuator is recommended.
If you are thinking about buying a KWM-380 I would suggest choosing one that has a higher serial number, 1500 and up or make sure that transceiver you are buying has all of the 18 service bulletins installed.
I will never part with this KWM-380/HF-380, so my recommendation is if you can find on in good operating condition buy it, you will not regret the decision. Current prices for a CCA very good to mint condition KWM-380 are in the $2500 to $4000 price range. |
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| N2FQ |
Rating: |
2012-05-09 | |
| Excellent |
Time Owned: 0 to 3 months. |
Sorry to have sold mine years ago, I have been fortunate
to pick one up recently. Easy to operate, similar performance
to my Orion and it's military grade. No band changing, super
receiver, razor sharp filters and love that PBT.
Fernando N2FQ/6 |
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| KX7P |
Rating: |
2010-12-01 | |
| CLASSIC PERFORMER |
Time Owned: 0 to 3 months. |
The KWM-380 is a classic performing HF radio with a classic radio look. It was built to last. Nothing cheap about this American made radio. It's not complicated to use. It has good size knobs and buttons on the front panel and a large digital frequency display. The receiver is great and compares well with many newer radios. It produced quality audio from the front mounted internal speaker, but I get better audio from a good external speaker. It has great transmit audio and I get many unsolicited complements on my audio.
The KWM 380 is a very expensive radio on the used market, but if you get one that has not been abused it should last the rest of your life. |
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