#Heathkit cr 1 crystal radio manual how to#
#Heathkit cr 1 crystal radio manual series#

The omnipresent Ham Radio operators in the Signal Corps probably helped, applying their skills of the day. This was early 20th century technology and any self-respecting GI was up on it. IвЂ™m not interested in those things, but I digress). They were the equivalent of todayвЂ™s techno-geeks and computer hackers (but not the modern kid who thinks вЂњcommunications technologyвЂќ is poking their finger at the screen of a Chinese-made iPhone.

#Heathkit cr 1 crystal radio manual how to#

The radios were built by the young GIвЂ™s who just knew how to make such things. That perforated Messerschmidt or Betty could also be a source for the necessary wire for the antenna tuning coil and antenna. The radio could be built from basic scrap, with the exception of the earplug or earphones those could be liberated from that enemy tank or aircraft wreckage. They were built and used during the time spent in the вЂњWaitвЂќ part of вЂњHurry up and WaitвЂќ. These Fox Hole radios did not require batteries вЂ“ they were powered by the signal from the distant radio station as collected by the receiver antenna. The BBC, Radio Australia and US Armed Forces Radio Stations would carry news from home, music and the all-important sports scores. Although the enemy propaganda was laughable, those stations attracted GIвЂ™s with their popular music pumped out by powerful radio transmitters.

вЂњ If itвЂ™s stupid вЂ“ but works вЂ“ it isnвЂ™t stupid вЂњ MurphyвЂ™s Laws of CombatДuring WWI, WWII and later conflicts, many GIвЂ™s built вЂњFox Hole RadiosвЂќ to listen to news, music, Tokyo Rose, Axis Sally, Lord Haw Haw and probably Hanoi Hannah too. IвЂ™ve built a lot of crystal radios but this one still works the best due to careful antenna вЂ“ diode вЂ“ headset impedance matching.

A crystal radio would have been very handy at that point.ДЇun times вЂ“ I still have the CR-1 and it still works great although the H-43/U headset shown above is not original. The transmitting sites would change every several minutes as they broadcast emergency information messages. Measures taken by the USG to prevent Soviet bombers from homing in on our AM broadcast transmitters as the Imperial Japanese Navy did during the attack on Pearl Harbor. These markings were required on all radio receivers built between 19, including this one. Those little CD (Civil Defense) markings were the frequencies set aside (6 KC) in the AM broadcast band for CONELRAD alert messages. Note the markings on the right-hand вЂњDETвЂќ dial. Here's a link you may find interesting.WrongвЂ¦.(IВ learned after looking through a Heathkit catalog that that feat would require a radio TRANSMITTER! I would drool over actual transmitters in the catalog that could do this вЂ“ like the DX-100 which I would eventually own). Of course one could use a larger box or switch to tiny poly-variables that would provide sufficient space for Tuggle style antenna tuning.

However, in this size housing, retaining the switchable fixed caps to tune the band is probably the easiest option.

#Heathkit cr 1 crystal radio manual series#

Series tuning isn't my favorite since it requires a wide range of capacitance and/or inductance (preferably both) to adequately tune the MW band. ceramic variable capacitors and include a tiny Ocean State type transformer for SP phones, along with an FO-215 diode. There are a number of ways one could do this.

The detector coil would be mounted at one end of the box and the antenna coil mounted on a slide to vary the coupling by translating the antenna coil along the side of the box for max/min coupling. To accomplish this I'd wind two medium strand count litz coils on 2' long ferrite rods and locate them at the bottom of the case, away from the caps and on opposite sides of the box. For starters, it's a decent set but a compromised design which could be improved with the addition of variable coupling between circuits. 'Anyone else care to critique this circuit-pros AND/ OR cons ?' I always wondered how many AM stations will still be on the air after the Soviets dropped 600 or 800 Hydrogen bombs on the lower 48 states.'ДЄs KR1S has said, 'getting news from the radio would be the least of your problems!' I agree. 'I love the ruggedness of this rig and the fact that it is BY far the best 'bomb shelter class' xtal set I've seen so far.

Heathkit cr-1 crystal radio manual