The Birmingham age-herald., 1922-08-13
DOTS AND DASHES

DO1S AN.
 You fellows who have not had your name In the Dots and Dashes column of the Radio page. drop us a line" we will be very glad to hear from you.
 Earl Dodge. 7312 First avenue, tells us that he has a short wave regen- erattve set which he constructed himself. He uses tlckler coil with the Armstrong feed back" regenera- tive hook up." Dodge also tells us that he has two-stage audio fre- quency amplifier which he built and uses in connection with his set.
 The Radio Digest publishes every week list of the broadcasting sta tions in the United States that have licenses. It looks good to see the list now, as Birmingham has twice as many broadcasting stations as any other city in Alabama. The list reads as follows:
 Alabama
 Birmingham, W I A G, WSY.
 Mobile, W F A P
 Montgomery. W G II.
 c. D. Butterfield of Chicago states that he has new circuit that ena- bles amplification without the use of vacuum tubes. This of course makes the set very inexpensive. These am plltiers are for crytaI sets only and they require three crystal detectors in the circuit. The inventor states that these amplifiers do not amplify the signals received or increase the range of the receiving set like a tube amplifier but that they do help the range a mile or two, and they about double the strength of the signals. This set will bring much aid to those who have crystal receivers and who have not the money to spend on a real amplifier. MT. Butterfield states that the new amplifier amplifies without distortion. The set Is quite simple in construction and requires only one battery, which is 22H volt "B" battery as used on the de- tector bulb of receiving set We will answer any questions about this set at the demonstration Saturday morning. This, as all the other de- monstrations, will be held at The Age-Herald building at II o'clock. If you want to put an amplifier on that crystal set without much ex- pense come down next Age-Herald Radio day and We will tell you all about it.
 The Knight Hardware and Electric company. who have given away three radio sets at the demonstra- tions they have had at their store, gaveithe last one to Howard String fellow, S25 Twentieth street, south. These demonstrations will be discon- tinued for week or two.
 The radiophone station at Knights has received government license. The call is 5 S. William Neville, who built and operates this station, states that he will greatly appreciate any reports from those who are hear ing his station and that he wishes to thank those who have already given him such information.
 Adam Engle, Ferty-eighth street, north, has home made crystal re- ceiving set which is giving him fine results.
 Frank Carlton, Central Park, has a crystal set.
 Manuel Smith has a crystal receiv- ing set. He lives on Twenty-first street, north.
 Mario Benham. 21s Forty-eightn street, north. has a set which he states gives most satisfactory re- suits. The tuning of this set Is made of spider-web coils, which were wound by the owner. There are three of these--one primary, one second ary, and one is used as a ticker coll. This set Is for short waves and Mario has two-stage audio- frequency am- plifier to be used in connection with the set.
 We have question from R. H. of Birmingham. The question asks for information about-a radio set de- signed for the Boy Scouts. If the writer will write us again, telling ex- actly what set he is referring to. we will gladly give him his desired in- formation. He also asks if he could use a toy transformer to cut down the 110 A. c. to eight volts, instead of using batteries. This is a question which is probably asked more than any other by the ones who are just starting. The answer is NO, and in- stead~of just saying no and give no explanation. we will try to explain. The current on both the plate and filament of the detector or amplify- ing tubes must be direct current and cutting down the current by toy "step-down" transformer does not rectify 1t. Therefore this transformer cannot be used to any advantage along this line. The writer seems to be under the impression that it takes eight volts for the filament, but this will prove fatal to the bulb as it Is too much current. Only use six volts on the filament of the bulbs on your receiving set. There are some de- vices that are supposed to make It possible to use the 110 A. c. for this purpose, but they do not and cannot eliminate the A. c. hum, which inter- feres greatly.
 Highland Park has few radio bugs who add something to their crystal sets quite often. Buck Harris has just completed a loose coupler, which he will use in the place of the old tuning coil on his crystal receiv- CT. Archibald Grubb, another one of the Highland Park fans. has built .