Patent US3858128A successfully refreshed from Google Patents.
US3858128A
Expired / Lapsed
US
⏱️ 0.0 years remaining
1 db step attenuator
Assignee: Textron Inc
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Filing: 1974-02-04
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Granted: 1974-12-31
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Expires: 1994-02-04
Abstract
Abstract An attenuator for audiometers and including a 5 dB step attenuator ladder, additional 1 dB step attenuator resistances connected in series with each other and connected by means of switching areas and wiper contacts moving over such switching areas of a switching plate to sequentially connect all of such resistances in series with the attenuator ladder and progressively short each such resistance out of the attenuation circuit as the wiper contacts move across the switching areas and thereby obtain a 1 dB step attenuation while maintaining the large increments in the 5 dB step attenuator ladder.
Inventors
- 👤 C Mullin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:01
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/24
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
185 words
An attenuator for audiometers and the like having an input and output, comprising: a large increment attenuator ladder having ladder segments and connection points between such segments to produce large increment dB attenuation change at adjacent connection points; a minute increment attenuator including a plurality of seriesconnected resistances and having rigidly interconnected wiper contacts connected at the ends of the several resistances; said output and input being applied to the terminal end of the attenuator ladder and a terminal end of the series-connected resistances; and a switching plate having a plurality of adjacent conductive switching areas over which such wiper contacts pass in succession, each of said conductive areas being connected to a respective connection point of the attenuator ladder, said conductive areas and wiper contacts being shaped and arranged relative to each other whereby as the contacts move over such an area, the contacts sequentially engage the conductive area to sequentially change the number of such resistances in series with a particular connection point of the attenuator ladder, and to repeat the sequence of engagement as the contacts move to an adjacent conductive area.
Claim 2
Dependent Claim
185 words
An attenuator for audiometers and the like having an input and output, comprising: a large increment attenuator ladder having ladder segments and connection points between such segments to produce large increment dB attenuation change at adjacent connection points; a minute increment attenuator including a plurality of seriesconnected resistances and having rigidly interconnected wiper contacts connected at the ends of the several resistances; said output and input being applied to the terminal end of the attenuator ladder and a terminal end of the series-connected resistances; and a switching plate having a plurality of adjacent conductive switching areas over which such wiper contacts pass in succession, each of said conductive areas being connected to a respective connection point of the attenuator ladder, said conductive areas and wiper contacts being shaped and arranged relative to each other whereby as the contacts move over such an area, the contacts sequentially engage the conductive area to sequentially change the number of such resistances in series with a particular connection point of the attenuator ladder, and to repeat the sequence of engagement as the contacts move to an adjacent conductive area.
Claim 3
Dependent Claim
65 words
The attenuator according to claim 1 and said wiper contacts being arranged in and to move in a line abreast, the conductive areas of the switching plate having individual contact areas each along the course of movement of a particular wiper contact and each contact area being displaced relative to adjoining contact areas in a direction along the course of movement of the wiper contacts.
Claim 4
Dependent Claim
33 words
The attenuator according to claim 2 and each of the conductive areas of the switching plate having a stepped leading edge defining such individual contact areas which are displaced relative to each other.
Claim 5
Dependent Claim
50 words
The attenuator according to claim 1 and said plate also having an additional elongate unbroken input signal conducting area extending along and adjacent the conductive switching areas, and an additional wiper contact moving along said elongate signal input area and connected to the terminal end of such series connected resistances.
Claim 6
Dependent Claim
62 words
The attenuator according to claim 2 and the contact areas of each conductive switching area having various spacings from the next adjacent conductive switching area, the contact area of each conductive switching area which is closest to the next adjacent conductive switching area being engageable with a partIcular wiper contact which is connected to said terminal end of the series connected resistances.
Claim 7
Dependent Claim
89 words
The attenuator according to claim 5 and said contact area of each conductive switching area which is closest to the next adjacent conductive switching area being displaced, in a direction extending along the course of movement of the wiper contacts in overlapping relation with said next adjacent conductive switching area whereby the plurality of wiper contacts in line abreast will simultaneously engage a pair of adjacent conductive switching areas during movement of the wiper contacts in transition from one conductive switching area to the next adjacent conductive switching area.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |