From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
'Philco Serviceman and Radio Manufacturers' Service News' bulletin discussing valves, batteries, and troubleshooting.
| Identifier | ExFiles\Box 63\3\ scan0307 | |
| Date | 1st March 1935 | |
| [Stamped in red ink] ROYCE LTD RECEIVED 9 APR 1935 PHILCO SERVICEMAN and RADIO MANUFACTURERS' SERVICE NEWS PHILCO VALVES We need offer no apology for introducing Philco Valves into the “Philco Serviceman,” for, as every good dealer knows, a part of his service to the public must be the ability to be able to supply spares, and particularly Valves, with the minimum delay to his customers. Those who keep their good name for being able to supply from stock will eventually—we might say in the very near future—capture the major portion of this really worth-while business for themselves from the community they serve. The stocking and selling of Valves is often considered a nuisance and an unprofitable occupation in some quarters, but the sale of Valves is highly profitable, especially when you can consider that the sale of an average of 15 Philco Valves represents more profit to you than the sale of the average 5-valve superhet, and added to this there is no possibility of the valve itself requiring servicing if it is a Philco Valve. Naturally, of course, the sale of Valves follows the sales of sets, and in this direction we would commend to your notice a scheme which has proved its value time and again, and that is to drop a line to people who have bought sets from you eighteen months or so ago, suggesting that you test their receiver. Generally it will be found that the sale of a valve can be effected; even if no sales result, your good will has been enhanced considerably, as your customer feels that you are taking a keen interest in his receiver. We would urge you, therefore, to place yourself in a position to give your customers real Valve service. So-called Adaptors and so on give entirely false readings when applied to modern superheterodynes, and the only possible test is an operating test such as can be given by the Philco 048A Signal Generator Set and Valve Tester. It is a test which, when applied in the presence of a customer, is not only convincing but a definitely truthful representation of the condition of his valves. The 048A can be made to pay for itself in a very short space of time when used for selling valves only, let alone its extreme usefulness for service repair work. New Valve Bulletins giving characteristics of all the next few posts. We would ask you to examine carefully the characteristics of these Valves, especially in view of the fact that a lot of interest is now being taken in L.F. amplification. To start with, the Rectifier Series is not equalled by any other line of valves; for example, the 5Z3 will give you ¼ amp. at 500 volts rectified current and the price is only 11/-. Another example is a pair of 2A3’s will give you 15 watts undistorted output with only 300 volts on their anodes, which means that Philco Electrolytic Condensers can be used for smoothing, which are very cheap compared with the high voltage paper condensers normally associated with amplifiers giving output of this type. Another Valve for Class “B” work is the type 59, two of which will give 20 watts undistorted output. Suitable valves for preceding these are types 56, 76, and so on. For further information on any valve in the Philco range, their application, etc., please write to the Special Equipment Department, at Perivale. HIGH TENSION BATTERIES The High Tension Batteries for the Model 233 are guaranteed by Messrs. Britannia Batteries, Ltd., and for the Model 233 by “Drydex” (The Chloride Electrical Storage Co.). Should it be necessary to return a battery for any reason the question of its return should be taken up with your Distributor and the Battery Manufacturer. Batteries should not be returned to Philco. One of the Directors of the B.I.E.T., Ltd., tells us that “Enrolments are still coming in from Philco Dealers and their Service-men, and our Technical Director informs me that most of the students are proceeding most enthusiastically with their studies.” QUESTIONS AND ANSWERS Q. I am experiencing “break-through” on my Philco Model 260. What is the cure? A.{Mr Adams} It is possible that this may be cured by redressing the wiring from the wave change switch to the aerial coil, or alternatively by substituting the 6A7 valve from another chassis. Q. How do I tell when the High Tension Battery of my Model 238 requires replacing? A.{Mr Adams} Owing to the curve of the type 1A6 frequency changer, when the High Tension Battery becomes exhausted, reception will become almost inaudible. Until this occurs no loss of performance will be noticeable. Q. Bad hum occurs on my receiver when it is tuned to a strong carrier. Can you suggest a cure? A.{Mr Adams} The hum you are experiencing is known as “modulation” hum, and can usually be eliminated by the insertion of a small condenser (approximately 700 mmf.) in series with the aerial lead-in. PAGE 4. MARCH, 1935. | ||