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A few of the radios which spent some time in my shack, from the late 50-ies to date.
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In the period 1956-58 I built several transmitters for HF and 144MHz, around PA valves like LS50, 2x807 and 2E26 (2m). My HF transmitters contained homebrew VFOs with one exception - a Geloso subunit. In 1957 I got my Norwegian ham certificate and license as LA8ZF.
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1957 HOMEBREW TRANSMITTER - CW/AM/FM
As LA8ZF in 1957, from left to right:
(1) A slightly modified 3-6 MHz receiver E10K (S-meter added)
(2) RX converter with RF stages, for 7 and 14 MHz
(3) 100% homebrew TX cabinet with:
- Colpitts VFO
- Multipliers
- 2x807 PA
- A3/FM modulators
- Power supplies
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1957 QSL CARD
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My first QSL card, printed in 1957, the same year I received my Norwegian ham license as LA8ZF. The receiver mentioned on the card was a homebuilt monster, later replaced by the E10K and converter
Already in 1958 I moved to Sweden, where Swedish citizenship was required to qualify for the license.
Only in 1963 the reciprocal licensing was introduced, allowing me to register as SM5HF.
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The receiver base was a WW2 German Luftwaffe surplus unit, the compact 3-6MHz "E10K", with supplementary homebuilt converters for other bands.
This photo shows the original exterior. I repainted the unit and added an S-meter (se the above station picture).
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WW2 RECEIVER E10K
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Rear view with cover off. All valves were of type RV12P2000.
More on this radio on the LA6NCA home page. Early 1958 I replaced the E10K by the National HRO-60, for the HF bands. The E10K stayed as IF for the 2m converter.
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WW2 VALVE RV12P2000
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Valve, and valve in socket. The RV12P2000 was a "Jack of all trades" and served in any low-power functions in German WW2 receivers and transmitters.
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The E10K tuning capacitor was machined out of solid aluminum blocks, and may be unlike anything you have seen. Photo LA6NCA.
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E10K TUNING CAPACITOR
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NATIONAL HRO-60
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In its time, the HRO-60 was considered to be top of the line. However, it left a lot to be wished in terms of SSB reception. The WW2 E10K could boast of a much better frequency stability.
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In April 1958 I moved from Norway to Sweden. At the time, reciprocal licensing was an unknown service and I had to wait until 1963 before being licensed as SM5HF. Kit building was a widespread occupation in the 60-ies. A number of Heatkits were assembled in my shack.
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The HW7 did fit the description of a minimum transceiver. Nevertheless, with a reasonably efficient antenna it may be good for DXCC on CW, although receiver sensitivity was not its strong side.
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HEATHKIT HW7
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The "Benton Harbour lunch box" became the next kitbuilding project. The HW30 still resides on the museum shelf in my shack.
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HEATHKIT HW30
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With AM in the 2W (input) region and a superreg receiver, you would not expect much result from the HW30. However, connected to a 4 over 4 skeleton slot antenna, it fetched a 144MHz phone signal report of 58 from Lillestrøm in Norway, close to a 450km span. The band conditions were, of course, above average.
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During a short period in the middle of the 60-ies, the Swedish military set RA200 AM/CW transmitter/receiver served in my shack. It was soon abandoned in favour of my first HEATHKIT transceiver, the HW12.
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HEATHKIT HW12 was a single-band transceiver, covering 80m. I loved it, which may be my reason for still hanging around in that band during most of my time - but now in front of a multiband rig.
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HEATHKIT HW12
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HEATHKIT HW32
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My reason for building the HW32 must have been an urge to try the 20m band. Frankly speaking, my memory is blurred when it comes to remembering its pros and cons. Anyhow, I got rid of the HW12/32 twins as soon as I finished the HW100 assembly.
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My 2m interest suddenly peaked, and I built a PA unit for 700W input, and an SSB exciter to go with it. Later, I sold the PA. It first went to SM5BQR, then I lost track of it.
Today, I would like to borrow or buy it back to take some better photos. If you recognize it from the below picture, please let me know. I am also looking for a copy of the QST December 1961. If you have one, I am prepared to buy it.
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The tank circuit consisted of two solid 2 inch brass tubes fitted around the push-pull 4CX250B anodes, doubling as ducts for the cooling air flow. You may find the construction article:
"Top Efficiency at 144Mc. With 4X250Bs"
in QST December 1961, page 44. Author Louis Breifogle, WØMOX.
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144MHZ 700W input PA
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The otherwise professional design had one flaw. The hi-Q tank circuit tuning drifted with temperature - and needed frequent adjustment. A larger cooling fan may solve that problem, but the fan I installed did already produce the air flow specified for 4CX250B tubes.
Today, only a couple of exciter circuit boards remain in my junkbox :
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MIXER AND AMPLIFIER
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The 100% homebrew board contains local oscillator, mixer and two amplifier stages. Output on 144MHz - a number of milliWatts to excite a separate driver unit, now missing.
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Not really homebrew. I purchased the empty PCB plus the 9MHz crystal filter - and completed the board with components from my comprehensive junkbox.
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9MHz SSB GENERATOR
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On the shortwave side, when the HW100 multiband SSB transceiver kit became available, I went for it. It was easy to build, and worked well from the first day.
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HEATHKIT HW100
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The HW100 was an amazing product in its time. We did not mind to wait half an hour or more, for the temperature to stabilize and the VFO drift to slow down. That was considered normal, before the advent of frequency synthesizers.
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In 1966, I obtained a permit to operate as SM5HF/SP3 from Poznan, Poland.
The rig consisted of the ST1200 1.5kW marine transmitter (left) - and a prototype SSB receiver of Polish design. It was a very good receiver, although it never came into series production.
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STANDARD RADIO ST1200
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How come the Polish receiver did not reach the stage of series production? Well, it had to be approved by the Polish Register of Shipping.
The prototype was approved, but the Register decided that the producer did not have the required testing instruments - needed to guarantee the exact duplication of prototype parameters. An understandable decision.
However, at that time, factories in Eastern Europe had to fight the bureaucrats. Once when I visited the polish factory producing marine receivers, hundreds of unpacked but apparently completed AM/CW receivers occupied the floor of a storage hall.
When I asked why, I was told that one resistor of a particular type was missing in all the receivers. That's not much of a problem, I said, give me a specification and I can ship the resistors within a few days.
No, was the answer, "the Anti-import Commission refuses to let us have an import license - because resistors of this type are produced in Poland".
A new license application had been submitted, adding important information: "the Polish resistor factory cannot deliver until 4 years after order".
The Commission bureaucrats answered promptly: "that's your problem, you should have ordered the resistors 4 years ago".
No import license was issued.
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1966 POZNAN QSL CARD
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Fisheries Exhibition QSL card, Poznan 1966.
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From about 1970, my job sent me abroad for a major part of the years, not much time for hamming. I let most of the home shack contents go.
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The VHF FM transceiver STR15 was designed for the marine band 156-164 MHz. Close enough for modification to the 2m ham band. I changed it to become a 12-channel ham FM transceiver, and named it TR15.
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STANDARD RADIO STR15
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ICOM IC-202
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In 1976, the IC-202 (144MHz) became my first factory-made transceiver, an SSB/CW rig with a low-noise receiver and about 3W PEP output. Apart from the lack of frequency setting accuracy, the '202 was a nice piece of equipment.
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After a long period of non-activity, my hamming interest grew to the point where I bought the IC-737, in the middle of the 90-ies.
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The IC-737 had most of the features you may ask from a modern HF transceiver, except DSP. Until replaced by the IC-756PROII in 2004, after 10 years, the '737 offered problem-free operation.
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ICOM IC-737
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Wanting DSP and the 2m and 70cm bands, I decided to purchase the IC-706 in 2003. Extra filters 1.9kHz (SSB) and 350Hz (CW).
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ICOM IC-706MkIIG
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The IC-706MkIIG is a nice little rig, functional in fixed as well as mobile service. The AT180 automatic tuner was added. On the shelf, I already had the AH3 tuner.
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Preparing for daily contacts with S/Y Myjoy en route Stockholm-Greenland, the PTC-IIpro modem was installed for PACTOR II and III operation.
The later experience from using PACTOR convinced me that it must be the perfect system for large scale emergency operations. Text transfer is extremely fast and 100% error free - and signal levels down to minus 18dB S/N are supported. The QRM problems, suffered in connection with phone contacts, are absent.
The most impressing feature, however, is the possibility to connect by radio to Internet and the conventional E-mail network - via a system of about 50 voluntary ham repeater stations. PACTOR means world wide E-mail access, from cars, trailers and boats - as well as from utterly remote locations where no other communication means are available. PACTOR is the perfect medium for emergency operations.
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PTC-IIPRO
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With PACTOR III, the PTC-IIpro does maintain links under conditions with signal to noise ratios of minus 18 dB, transferring error-free data even when the signals cannot be perceived by the human ear.
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The extreme power and antenna combinations used by a multitude of hams in Central and Eastern Europe can make it difficult to keep an 80m frequency for more than a few minutes. That is, unless your transmitting power is large enough to make it obvious that the frequency is occupied. A Power Amplifier seemed to be the solution.
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A single GU74B (4CX800A) ceramic tetrode delivering up to 1kW to the antenna, all modes and bands 160 to 10m. On 6m, local regulations set a limit at 300W ERP. The ACOM 1000 protection circuits make it virtually foolprof, and its tuning indicator allows in-band tuning to be completed in 5 seconds.
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ACOM 1000 POWER AMPLIFIER
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The IC-756PROII had tempted me for a long time. When I got a tax restitution that covered the purchase, I rushed to place my order before my conscience told me that the money could be used for better purposes. After all, the IC-706MkIIG performed remarkably well as main HF transceiver - but is now reserved for PACTOR service.
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ICOM IC-756PROII
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The '756 was installed end of February 2004.
So far, it has worked like a charm. The real-time spectrum scope is a hit.
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If the '756 spectrum scope is a great asset on the HF bands, it is an even greater asset on 144MHz. Being able to see 2m stations pop up anywhere within a large portion of the band - without touching the tuning knob - is one very good reason for using the '756 with a 2m transverter.
A good thing, however, can be made better. Wanted: a USB-connected mouse, to click on any visible signal in the spectrum, for immediate frequency selection.
I connected the '756 to a computer via the CT-17 level converter, and installed the "Ham Radio Deluxe" software. The HRD provides mouse-controlled frequency selection but only as an emergency solution. The '756 spectrum scope offers only approximate frequency information, extracted by mental interpolation. The HRD needs more accurate input to synchronize with the scope frequency data.
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In 1991 I retired from my main job. In the beginning of 2005, I reached the considerable age of 75 and decided to retire from part time office work too - to concentrate on ham activities. For 2006, I added a transverter for 2m. And a 2m PA.
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KUHNE TR144H TRANSVERTER
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For serious VHF operation, one would need a little more power than the 25W produced by the transverter. The TE SYSTEMS 1452G 2m power amplifier seemed to qualify - the manufacturer did promise 400W to the antenna. However, after a blown power transistor I gave it a personal rating of 300W.
The manufacturer specifies driving power 10-25W. First time, I set the output from the transverter to 10W in a 50 Ohm dummy load, before connecting it to the 1452G. It became immediately apparent that 10W was far too much drive. I quickly reduced it to less than 5W which seemed more appropriate, and the PA did seemingly work OK. However, damage was already done. After a few days, one of the power transistors died.
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TE SYSTEMS 1452G
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In spite of the apparent misinformation concerning required driving power, the 1452G has worked without further problems - after replacing the blown power transistor. This amplifier is lacking protection circuits and must be handled with care.
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I was looking for a VHF/UHF FM transceiver to install in my car. The ICOM E208 looked like a good choice for mobile use. Disadvantages considered: analog and not compatible with digital equipment, no VOX. Advantage: low price.
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Small dimensions, 55/50W output power, detachable front panel (W111 H40 D26.3mm) and 144/432MHz coverage.
Cloning software and cable from www.rtsystemsinc.com.
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IC-E208 VHF/UHF FM TRANSCEIVER
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