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Simple but nice receiver with metal/ plastic combination on the front and black horizontal cabinet with telescopic antenna and wrist estrap .
The chassis has eigth transistors: four of germanium in the AF amplification stages; and four very small silicon wafer type in RF/IF stages. I have seen these small silicon transistors in audio stages of the MICRONIC RUBY sets.
It requires a 9V square battery or external DC 9V and works well on both bands.
Geranium. District population 83.
The Hundred of Price was declared in 1906 and the town for the Hundred was to be Geranium. Its location was based around a government bore sunk in 1897 for future farmers on a site of a water soak known to the Ngarkat people. The district was surveyed in 1906 after the rail line had been completed but the first town lots did not sell in the newly surveyed town of germanium until 1910. It was named after the wild geraniums of the district.
From its beginnings in 1910 Mallee stumps and roots were railed back to Adelaide from Geranium and elsewhere. Eudunda Farmers had a weighbridge installed at Geranium in 1911, the same year that they opened a General Store in the town. It was the 10th Eudunda Farmers Store in SA on the corner of Railway Terrace and Price Street. The first settlers included a mix of English and German background families. Apart from new disease resistant wheat varieties a lot of oaten hay was grown in the district. This was still the era when farmers had teams of six to twelve draft horses to pull the Mallee rollers and wheat ploughs and harvesters. Some areas were lucky enough to have tea tree suitable for the brush fences of Adelaide suburban houses! As the town emerged a school opened in 1912; Methodist Church services began in 1910 in the Institute; the timber framed Methodist Church opened in 1954; an Anglican Church was built south of the railway line in 1968. The Anglican Church is now the Post Office. A galvanised iron Institute for community social functions was quickly put up in 1909 with a new solid stone replacement Institute opening in May 1922. It was built in front of the old iron hall which was demolished in 1952. The stone Institute was demolished in 2006 but it used to stand opposite the current memorial cairn on Railway Terrace next to the original Eudunda farmers store. The Geranium Area School catering for high school students opened in 1965 with 247 pupils. Geranium only just survives as a town. The school was downgraded from an Area school to a primary school in 1990 and now it is closed despite two large classroom blocks and other facilities. It closed in 2022. Students can be bussed to Lameroo Area School. Some years ago when the general store was put on the market and no buyer could be found the town bought the store and operated it as a community store. This store was the second store built for Eudunda Farmers in 1963. It is now permanently closed. The 2021 census recorded 83 residents for the town. Although Geranium is a 20th century town it had a number of structures on the Register of the National Estate including the 1922 Institute and the railway station site and the town bore sunk in 1906 - but these buildings are now gone.
Near-infrared thermal radiation from the night side of Venus
Credit: Giuseppe Donatiello
The surface of Venus can be observed on the night side using several windows in the near-infrared wavelength range.
The intensity of the thermal emission is controlled by the emissivity and temperature of the surface. The radiative transfer model of Venus' atmosphere shows that it is sufficiently transparent at these wavelengths to allow the contribution from the surface to be transmitted through the clouds.
Thermal emission from the night side of Venus has been observed at 1.0 micrometers (1000 nm).
The image was captured during the great Venus-Jupiter conjunction on June 30, 2015 with a 114/900 Newtonian optimized for planetary observation using a DIY NIRCam 1280 astrocamera equipped with a 1000nm Germanium filter.
Images included in Mystery of the Ashen Light of Venus by John Barantine: www.springer.com/us/book/9783030727147
Last edit: November 5, 2024
EDISWAN Germanium transistor originally from the late 1950s. The gain on this one is at the very top end of the gain spec @ 105.
Edison and Swan merged in the UK in the late 1800s when Swan already held the dominant patents for the incadescent bulb.
Ediswan were one of the original companies in the Associated Electrical Industries (AEI) merger from 1929 which included British Thomson Houston. Thomson Houston in the US became General Electric.
Many British lamp companies moved into valves (tubes). Indeed, the inventor of the first thermionic valve, Ambrose Fleming, worked at Edison Swan's factory at Ponders End in North London.
Siemens Brothers (the other brothers) merged with Edison Swan in the early 1950s.
It's not clear where Ediswan semiconductors were manufactured but may have been at Woolwich or Ponders End. Siemens Edison Swan had a research lab in West Road, Harlow in the late 1950s doing semiconductor research, which became the AEI Harlow Research Laboratory in 1961.
Talk about branding confusion -
Siemens Edison Swan Ltd...
An A.E.I. Company...
EDISWAN semiconductors...
And throw the Mazda brand in as well for good measure !
hfe=105, Vf=129mV. The part looks awfully new but I can’t imagine the transistor and box are copies.
AEI Germanium transistor from the late 1950s or early 1960s.
Ediswan were one of the original companies in the Associated Electrical Industries (AEI) merger from 1929 which included British Thomson Houston.
More info on Ediswan transistors and a badged Ediswan (almost) equivalent here :
Other AEI semicondutors and further history here :
pnp hfe=40, Vf=110mV
It is identical to MINIMAN ROCKET RADIO MG-306 "PIONEER", but with the cardboard box in blue, so I think it was manufactured by Miniman Radio Co., Ltd.
I like the green color cabinet of this desktop radio that works great on both bands (AM / FM). The front panel is made of acrylic and the volume and tone controls are sliding type. The printed circuit and dial rule are on the cabinet right side and the left side is empty with perforations, covered by the front acrylic, to accommodate an electric clock so this is an example of how the same cabinet was used for different versions. The chassis has eigth transistors: four of silicon for the conversion and intermediate frequency stages; and four of germanium for audio amplification stages. It is powered by 120 VAC.
This immaculate Ever Ready Sky Leader is another of the sets in my vintage radio collection. The Sky Leader was one of the very first transistor radios to be commercially available. The advent of semiconductors made radios truly portable for the first time, and battery manufacturer Ever Ready seized on the opportunity as a way to promote it’s battery products.
Produced by the Ever Ready Co. GB Ltd.; London, the Sky Leader is a six transistor two-band portable receiver radio. This particular example, which is in full working order, was originally owned by a gentleman in Newton-on-Trent, Lincoln and dates to the early 1960’s.
The Mullard transistors used in this radio are quite unlike modern transistors as they are semiconductors based on Germanium rather than Silicon. Germanium transistors operated on a different technological principle to their silicon successors, however, they proved immensely reliable and many sets like this one contain the originals.
In addition many audio specialists still today prefer the sound produced by Germanium semiconductor based amplification circuits over those which utilise silicon transistors. This preference gives rise to the term “Germanium sound”, as it is claimed that Germanium semiconductors produce a smoother and more acceptable distortion. For this reason amplifiers based on Germanium transistors are still in use, and original Mullard transistors sell rapidly on sites like eBay.
This radio also contains a high quality Celestion speaker. The Celestion company began manufacturing speakers in 1924, and is still operational today. Celestion speakers became known as the 'voice of rock & roll', and were the preferred choice of iconic musicians such as Jimi Hendrix and Slash. Their products installed in radios like this one, and earlier valve sets are still performing flawlessly many decades after they were produced.
Other components in this set such as capacitors were manufactured by Plessey, a company founded in 1917, and of course one which is still at the fore front of the electronics industry today.
Unlike the electronic component manufacturers, Ever Ready faced more difficult times, as eventually battery manufacture became a commodity and migrated to low cost manufacturing countries in the Far East. However, although not well known, Ever Ready has a strong link with Walsall, because in 1972 the company acquired J. A. Crabtree & Co, who had a factory in the town. However, Ever Ready (and indeed Crabtree) was the subject of a hostile takeover by Hanson Trust in 1981. The Hanson Trust effectively ended Ever Ready’s long history, and the last Ever Ready radios were produced in the early 1980s.
boston, massachusetts
1960
the birth of automatic test equipment
nick's own promotional pictures for teradyne's first product,
the d133 diode tester
nick's hand with suspended diode and the centerpiece of the diode tester
note "floating" diode!
part of an archival project, featuring the photographs of nick dewolf
© the Nick DeWolf Foundation
Image-use requests are welcome via flickrmail or nickdewolfphotoarchive [at] gmail [dot] com
Beautiful receiver for use only with earphone, in fact in the upper left has input for two and in the top center a connection for external antenna.
The large knob of the dial is painted on the back as well as red round Aiwa logo on the lower right side, and the front face of the cabinet looks elegant with that vertical and horizontal lines. It should be mentioned that it lacks CD marks, so I think that maybe it was not projected for the U.S.A. market.
The chassis has Toshiba transistors: 2S44; 2S49, 2S52; and a 1N60 germanium diode, requiring a 9 volts square battery for its power supply.
The assembly is on a fiberboard that has painted on the surface the location of the different components.
This receiver is obviously very similar to the Panasonic R-72 "TOOT-A-LOOP", however it is very well built with quality materials and still works occupying three 1.5V AA batteries. It is known as "The Bag" among Spanish collectors and in vintage advertising it claims to be the transformable transistor radio that can acquire a variety of original and decorative forms.
The chassis has six transistors: two germanium (AC-188) for the final transformerless audio amplification stage, and four silicon transistors (115A X 2, 115B and 109) for the other stages of this superheterodyne.
Internacional Radio Televisión S.A. It began its journey on December 15, 1948 in Barcelona, installing its commercial offices on 227 Rosellón Street, being the founder Don José Gómez Serrano, who was one of the founders of Iberia Radio SA, to later constitute INTER ELECTRONICA and INTERNACIONAL RADIO Y TELEVISION, whose presidency he held until the acquisition of the company by GRUNDIG, then becoming, with an honorary character, that of INTER GRUNDIG, S.A. so far his death on August 30, 1978.
This company manufactured a wide variety of tube receivers, televisions, transistor radios and even cassette players.
Askar was a brand of radios manufactured in Irún (Guipúzcoa) by Industrias Radioélectricas Gortari. This company was founded by José Gortari in 1934. Subsequently it changed its name to Industrias Radioeléctricas IRESA S.A., and in the mid 1950´s it joined with RADIO CASTILLA ( Philips), which gave origin to that the musical symbol, distinctive of the ASKAR brand, was inserted inside the Castilla coat of arms.
This multi-band receiver (OM, OC1 y OC2) with a trapezoidal shape and two tone cabinet, clearly shows in its chassis the quality of Philips. It has six germanium transistors ( (3) AF117, (1) OC75, (2) OC74 ) powered by four 1.5V flashlight batteries. Has on the left side the ON OFF/VOL. knob, headphone jack and access to the compartment that holds the telescopic antenna. At the top is the rule dial scale, with the reverse side painted, and a metal knob to select the band and place the antenna. Also at the bottom, the base of the cabinet, has access to the battery compartment by means of a sliding strip. In this compartment is affixed the ASKAR tag with the type number and the payment of the luxury tax, as well as a small white label with the serial number.
This set has signs of being opened by someone inexperienced because it has some breaks in the edges of the cabinet, especially in the orange front cover, also seems to have been exposed to some heat source, perhaps sunlight, because the back cover shows these effects. Either way, it is highly collectible besides that still works very well with original electronic components.
quran
32:7 Who made all things good which He created, and He began the creation of man from clay;
Genesis chapter 2 verses 4 - 8
"In the day that God made the earth and the heavens, when no plant of the field was yet in the earth and no herb of the field had yet sprung up-for God had not caused it to rain upon the earth, and there was no one to till the ground; but a stream would rise from the earth, and water the whole face of the ground- then God formed man from the dust of the ground, and breathed into his nostrils the breath of life; and the man became a living being.
And God planted a garden in Eden, in the east; and there he put the man whom he had formed."
Man is created with exactly all the Macro minerals and Micro minerals we also find on the earth. We are actually built with the material that already were on this planet. So here we go:
Most of the human body is made up of water, H2O, with cells consisting of 65-90% water by weight. Therefore, it isn't surprising that most of a human body's mass is oxygen. Carbon, the basic unit for organic molecules, comes in second. 99% of the mass of the human body is made up of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.
Macro minerals in us are:
1. Oxygen (65%)
2. Carbone (18%)
3. Hydrogen (10%)
4. Nitrogen (3%)
5. Calcium (1.5%)
6. Phosphorus (1.0%)
7. Potassium (0.35%)
8. Sulfur (0.25%)
9. Sodium (0.15%)
10. Magnesium (0.05%)
(Reference: H. A. Harper, V. W. Rodwell, P. A. Mayes)
Also we are created with these Micro minerals in us:
Iron, Fluoride, Zinc, Rubidium, Strontium, Lead, Copper, Aluminium, Cadmium, Barium, Cobalt, Vanadium, Iodine, Tin, Selenium, Arsenic, Manganese, Mercury, Nickel, Molybdenum, Chromium, bismuth, Lithium, Uranium, Boron, Germanium, Bromine, Gold, Silver, Beryllium, Antimony and Thallium.
n the Babylonian creation epic Enuma Elish, the goddess Ninhursag created humans from clay.
In Africa, the Yoruba culture holds that the god Obatala likewise created the human race.
In Egyptian mythology, the ram-headed god Khnum made people from clay in the waters of the Nile.
In Chinese myth, the goddess Nuwa created the first humans from mud and clay.
According to Genesis 2:7 "And the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul."
According to Qur'an[23:12–15], Allah created man from clay. See the Quranic science of Embryology for full details.
Mayan myth holds that Tepeu and Kukulkán (Quetzalcoatl) made the first humans
Tepeu and Gucumatz hold a conference and decide that, in order to preserve their legacy, they must create a race of beings who can worship them. Huracan does the actual creating while Tepeu and Gucumatz guide the process. Earth is created, but the gods make several false starts in setting humanity upon the earth. Animals were created first; however, with all of their howling and squawking they did not worship their creators and were thus banished forever to the forest. Man is created first of mud, but they just crumbled and dissolved away.
A West African creation tale explains how two spirit people were accidentally sent down to earth by the sky god. Lonely, the people decided to create children from clay, but feel they must hide them when the sky god comes down. Because they are hidden in fire, the children soon turn to various shades based on how long they had been exposed to the heat. Over time, these clay children grow up and move to various regions of the earth, ultimately populating it (Fader). Much like that of the Shilluk people, this story serves a two-fold purpose: it explains both the creation of man as well as accounts for the differences among him. This tale shows the West Africans value these differences because they feel that all men are created equal and should be treated as such.
Chewing Black Bones, a respected Blackfeet elder, told Ella E. Clark the following creation myth in 1953. Clark later published the account in her book, "Indian Legends from the Northern Rockies."
One day Old Man decided that he would make a woman and a child. So he formed them both of clay, the woman and the child, her son.
After he had molded the clay in human shape, he said to it, "You must be people." And then he covered it up and went away. The next morning he went to the place, took off the covering, looked at the images, and said "Arise and walk." They did so. They walked down to the river with their maker, and then he told them that his name was NAPI, Old Man.
This is how we came to be people. It is he who made us.
Kato (Mendocino County, California):
The previous world had a sky of sandstone rock. Two gods, Thunder and Nagaicho, saw that it was old. They stretched it, propped up its four corners, created flowers, clouds and other pleasant things. They created a man out of earth, putting in grass for the stomach and heart, clay for liver and kidneys, pulverized red stone mixed with water for blood.
source :
phoenixqi.blogspot.com/2007/04/many-men-of-mud-myths-from...
I heard a rumor that some of y'all like the sound of germanium fuzz pedals, but hate dealing with the strange reverse-polarity power adapters. Well, 2016 is gonna be a good year for cool fuzz pedals wearing a Fool logo! That's a thousand AC130 NPN germanium transistors, bro!
One of the first transistor radios manufactured in Italy. Beautiful blue plastic cabinet with metalic carrying handle, which folds down to fit on top of the cabinet, dial scale and knob painted on the reverse side and ON/OFF switch placed on top with a tab to activate. It requires six penligth batteries, but also can be powered with an adapter to the AC line, Model A-725, or in the car with the Model S-725 adapter.
Perhaps for being one of the first, the chassis has six RCA plug in germanium transistors ( 2N412, (2) 2N410 and (3) 2N408 ), instead of classics european transistors. Also, the chassis is composed of two modules: one circuit board for Converter, F.I. and detector; and a metal handwired board for audio frecuencies (Pre and Power Amplification).
Geranium. District population 83.
The Hundred of Price was declared in 1906 and the town for the Hundred was to be Geranium. Its location was based around a government bore sunk in 1897 for future farmers on a site of a water soak known to the Ngarkat people. The district was surveyed in 1906 after the rail line had been completed but the first town lots did not sell in the newly surveyed town of germanium until 1910. It was named after the wild geraniums of the district.
From its beginnings in 1910 Mallee stumps and roots were railed back to Adelaide from Geranium and elsewhere. Eudunda Farmers had a weighbridge installed at Geranium in 1911, the same year that they opened a General Store in the town. It was the 10th Eudunda Farmers Store in SA on the corner of Railway Terrace and Price Street. The first settlers included a mix of English and German background families. Apart from new disease resistant wheat varieties a lot of oaten hay was grown in the district. This was still the era when farmers had teams of six to twelve draft horses to pull the Mallee rollers and wheat ploughs and harvesters. Some areas were lucky enough to have tea tree suitable for the brush fences of Adelaide suburban houses! As the town emerged a school opened in 1912; Methodist Church services began in 1910 in the Institute; the timber framed Methodist Church opened in 1954; an Anglican Church was built south of the railway line in 1968. The Anglican Church is now the Post Office. A galvanised iron Institute for community social functions was quickly put up in 1909 with a new solid stone replacement Institute opening in May 1922. It was built in front of the old iron hall which was demolished in 1952. The stone Institute was demolished in 2006 but it used to stand opposite the current memorial cairn on Railway Terrace next to the original Eudunda farmers store. The Geranium Area School catering for high school students opened in 1965 with 247 pupils. Geranium only just survives as a town. The school was downgraded from an Area school to a primary school in 1990 and now it is closed despite two large classroom blocks and other facilities. It closed in 2022. Students can be bussed to Lameroo Area School. Some years ago when the general store was put on the market and no buyer could be found the town bought the store and operated it as a community store. This store was the second store built for Eudunda Farmers in 1963. It is now permanently closed. The 2021 census recorded 83 residents for the town. Although Geranium is a 20th century town it had a number of structures on the Register of the National Estate including the 1922 Institute and the railway station site and the town bore sunk in 1906 - but these buildings are now gone.
shot taken at CCQ restaurant, Aritao, Nueva Viscaya
Body: SR exfoh highdeck
Chassis: MAN 18.310
Engine: MAN D2866LOH27
former automatic.. now manual transmissino.. new engine from south star
This is a the "Mobile Phone" commercial use concept that existed in 1948. Motorola among many were in a battle for miniaturization, yet they were all still stuck in the pre-transistor tube/valve age. The dawn of a new era was at hand. Bell Labs, now know as Lucent Technologies, developed a promising three-terminal device constructed on a substrate of germanium along with other trace metals. It showed gain using very low voltages as compared to tubes. This two-way radio depicted above has a microphone/speaker shaped like a telephone handset. It is not full duplex: You have on the handset handle a PTT [Push To Talk} button bar to press in when you want to speak and to release to listen. Motorola recently tried to legally keep anyone from commercially using the term PTT that they use on their annoying cell "walkie-talkie feature" phones. They lost. BTW: Half of that box is full of Batteries. An "A Battery ", [4 to 12v] just for the tube heaters, and a "B Battery", for the actual working circuitry [likely 90v - 2x45v Batteries in series or as 1 unit].
Chances are that you now have not millions, but billions of transistors devices in your home and they ain't leaving.
Say Hello to the Transistor 1948.
A British radio from the late 1960s, early 1970s featuring four valves (tubes) single conversion - the MkII replaced a valve rectifier with solid state diodes.
With performance like this, it's no wonder the Americans and then the Japanese stole the market! I made a transistor superhet in the early 1970s from a design in Practical Wireless which performed better than this radio.
It's in fine mechanical condition, maybe a bit of "fettling up" will improve the performance, but I think it is basically an unremarkable design. You can only expect so much from a four-valve circuit.
There is no way you could use this for amateur communications when coupled with a transmitter, except perhaps on Top Band AM at a pinch ... Nice looking radio, though!
Described as a "communications receiver" in advertisements at the time - that's stretching the point a wee bit, in my view.
Circuit configuration :-
ECH81 "Classic" Triode/Heptode frequency changer (no RF stage)
EF183 IF Amplifier
OA81Germanium diode envelope detector (no product detector for SSB/CW)
12AT7 Audio preamp/AF output (dual valve)
12AT7 BFO/S Meter driver (dual valve)
Silicon diode rectifier for HT supply.
Very small germanium radio that looks like table top tube receptor, in fact in the ivory one, I put a ½ watt carbon resistor to compare dimensions. Indeed it is very similar to the Model GR-10, only with some differences in the front face, but sharing the same circuit and accessories, however I coud not find references on the web.
It seems that were highly popular herein in México City, because I have found it in different colors: blue, red, green and ivory; unfortunately by being aimed at children, it is difficult to find them in good condition and with their complete accessories.
The circuit is tuned with a ferrite slug that is driven by a clever rack and pinion mechanism. The crystal earpiece is CROWN RC-300, and the antenna cable plug is engraved with Japanese pictograps to indicate two choices for connecting the coil.
View of a small cottage in thermal imaging showing a mixture of effects - heat loss and some thermal gain from weak sunlight. The majority of the house is shielded form the sun by tall trees.
Image made using Therm-App thermal imager and Microsoft Image Composite Editor.
I found this receiver with its cardboard box, instruction and warranty policy, unfortunately the cardboard box is very battered and unpresentable, but I took pictures of some fragments that helped me to make a suitable frame for the AM receiver picture.
It works very well with its original electronic components. The chassis has a combination of silicon transistors (for the radio frequency and audio preamp stages) and germanium (for the audio amplification stages): BF494B, BF495C, 2 X BC558B, 2 X AC187, and AC188; powered by two "AA" size batteries.
National Mexicana, S.A., was founded in 1967 by Matsushita Electric of Japan and the mexican Grupo Industrial Guindi, locating the manufacturing plant in 22 Toluca Boulevard, Naucalpan de Juárez, Estado de Mexico. At the end 60´s and during 70´s National Mexicana, S.A., manufactured several models, from pocket to table top radios and some with turntable.
What's new:
* Lovepedal Eternity
* Lovepedal Black Beauty Balance
* Lovepedal Toxic II
* Lovepedal COT50
* Subdecay Blackstar
Already sold, but pictured in this photo:
* Lovepedal Black Magic
* Subdecay Blackstar
Although this AM receiver is not in good condition, it has some cracks and traces of the passage of time/use, it is highly collectable by its beautiful late 50´s design and be manufactured by TOSHIBA.
The slide rule tuning dial is painted on the reverse side making a perfect coupling with the large knob and loudspeaker grille with those inclined lines that delimit it and provide dynamism to the front face of the cabinet.
The chassis has six Toshiba transistors: 2S52, 2S53, 2S25, 2S54, 2 X 2S56; and a 1N60 germanium diode, requiring a 9 volts square battery.
GEC first developed transistor devices at their research facility in Wembley, then transferred production to the GEC Radio Works in Coventry, where a point contact diode line had been established.
In 1956 GEC established a dedicated semiconductor manufacturing facility at School St, Hazel Grove (Greater Manchester).
In 1962 GEC merged their semiconductor business with Mullard into a business called ASM (Associated Semiconductor Manufacturers), creating the UK's dominant semiconductor company of the 1960s. Mullard (Philips) owned 2/3 of the company. GEC devices were subsequently marketed as Mullard. GEC sold most of their share in 1968.
NXP (formerly Philips) still have an operating semiconductor facility in Hazel Grove.
pnp, hfe=125, Vf=121mV. RJ (on the body) could represent the date code, and if so it's 1963, week 10.
I have seen few receivers that have the cabinet made of semitransparent acrylic, this is one of them. Also they exist in yellow, but unfortunately were hard used so it is difficult to find in good condition. This item was no exception, it was falling apart when I bought it, as well as missing the speaker, it had corrosion in the battery holder and the circuit did not work. Because all cabinet parts were in good condition I decided to take the challenge to restore it and this is the result.
The cabinet is composed of five pieces of acrylic with grooves at the ends to fit and glue. The rear cover had broken the pressure lock with which it fits in place, so I had to make a new one. The front face of the cabinet is a single piece of clear acrylic that has stickers pasted on the reverse side (numbers, logos and lines) and the slots for the speaker. Once I restored the cabinet I had to paste it again.
The chassis was manufactured by Lombrozo Electrónica, S.A., and has seven transistors: four silicon [BF494B (Osc.), BF495C (F.I.), BF255D (F.I.) and BC238B (Audio Preamp)] and three germanium [(2) AC128 and (1) AC127] for the transformer-free audio output stage; powered by four 1.5V "C" size batteries. Finding the fault of the AM circuit was relatively simple, however getting the spare germanium transistor AC127 and the proper speaker, because it had to fit perfectly in the designated space, was something difficult but I finally got them and now it is working perfectly well.
Testing the translucent of some chips in the LWIR-band (8-14 µm). Intels silicon is still not transparent.
Photo of preamps used in drum mics and drumkit miking demostration focused on Joey Jordison snare drum, Pearl kick drum and using different microphones.
Snare, Kick, Drum mics & miking
snare, kick, drum, drumkit, drum kit, drum mics, drum miking, drum recording, snare mic, mics, microphones, recording studio
So this is a clone of the old Interfax Harmonic Percolator. I used a board from Fuzz Dog's Pedal Parts in the UK. I built this pedal using a vintage BC108 with an hFE of 284 for the silicon transistor and a vintage Tesla 104NU71 with an hFE of 60 for the germanium transistor.
It's...odd. Sometimes strange and splatty. Sometimes furry and warm. Switching out the diode clipping makes it even more obviously quirky. It's a very unusual fuzz pedal.