Thousands of Washington residents - from federal workers and merchants and bank presidents - are eagerly awaiting the arrival of November.

That is when the first installment of the new 7.05 per cent pay raise will actually show up in the local economy. Although it amounts to just a little over $12 per week (before taxes) for the typical clerk-steno at the Commerce Department, the total raise will be worth $50 million a month, every month, because 300,000 civilians and 60,000 military people here will get it.

Police units who try their best to keep banks from being robbed dread the Thandsgiving to-Christmas season when the money is flowing, and skimasks are reasonable attire on city streets. They are especially watchful when the government gets a pay raise here since banks beef up their stocks of money-on-hand to cash payroll checks.

Although military personnel will get their raise effective Oct. 1. civilian employees don't begin to earn it until the first pay period on or after that date. Although pay periods and paydays vary, federal officials say the raise won't kick in until Oct. 9 for most white collar workers. They will earn it for the full pay period ending Oct. 22, and then get it about 10 days later. That is the first week in November.

The 7.05 per cent raise was approvedby President after his advisers said that is the amount needed to bring most government wordersa (not top personnel) up to the national industry average for similar jobs. Since Washington is headquarters town for government, the federal white collar average here, where middle and top-grade workers abound, will jump to $20,800 when the raises become effective. nationally, the average white collar federal salary will be about $3,000 less than that amount.

The $3.5 billion price tag for the pay raise is huge. But more than half of it goes to military personnel. When broken down individually the 7.05 per cent doesn't seem like all that much. For example, here is the two-week payperiod breakdown (before taxes) for selected grades:

Grade 3 will to go up to a starting salary of $7,930. or $20 per pay period. Grade 5 will increase to $9,959, with a $25.60 biweekly increase for employees in the first pay step.

Grade 7 jump $31.20 per biweekly pay period in the first step, to $12,336.

Grade 9 gets a first-step increased of $37.60 (all these are befor taxes and deductions), to a starting salary of $15,090.

Grade 11 goes up $46,40 biweekly in the first step to $18,258 . . . The GS 13 increase is about $45.60 per pay period and Grade 15 will be up $92.00 each payday in the starting salary of $36,171.

Nobody can accurately assess the impact of a federal-military pay raise on Washington. But it is safe to assume that prices never have gone down as a result of an increase, even though it is around $2 per day for the lowest rank civil servant.

Pay Chart Ettor: The pay chart in yesterday's paper contained a misleading line. The dollar figures are correct. But the chart indicated that the 10 longevity steps within each grade are attained after 10 years service. Actually, it takes much longer to get to the top of the pay scale within each grade.

Only steps one through four are reached after one year of satisfactory service in each step. Steps five, six and seven each take two years and steps eight, nine and 10 take 3 years of service.

Dual Compensation: The chairman of the Civil Service Commission has urged Congress not to be hasty in cutting off pensions of retired military personnel who take second career jobs as federal civilians, Currently, more than 141.000 retired military personnel are working in government, most (except for retired regular officers) drawing full military pensions in addition to their federal salary.

The House Investigations Subcommittee is working on legislation that would eliminate some aspects of "double dipping", and CSC chief Alan Campbell yesterday recommended that it go easy. Campbell said the government could lose many of its most skilled employees if it forces them to give up earned military pensions.

He indicated that the Carter administration might go along with a pension limit for military personnel in government, but suggested it might be best to await the report of a presidential commission (now holding hearings in the Norfolk area) studying military compensation. That report is due by March. 1978.